Daily Archives: February 26, 2024

The fractional quantum Hall effect has generally been seen under very high magnetic fields, but MIT physicists have now observed it in simple graphene. In a five-layer graphene/hexagonal boron nitride (hBN) moire superlattice, electrons (blue ball) interact with each other strongly and behave as if they are broken into fractional charges. Credit: Sampson Wilcox, RLE

An exotic electronic state observed by MIT physicists could enable more robust forms of quantum computing.

The electron is the basic unit of electricity, as it carries a single negative charge. This is what were taught in high school physics, and it is overwhelmingly the case in most materials in nature.

But in very special states of matter, electrons can splinter into fractions of their whole. This phenomenon, known as fractional charge, is exceedingly rare, and if it can be corralled and controlled, the exotic electronic state could help to build resilient, fault-tolerant quantum computers.

To date, this effect, known to physicists as the fractional quantum Hall effect, has been observed a handful of times, and mostly under very high, carefully maintained magnetic fields. Only recently have scientists seen the effect in a material that did not require such powerful magnetic manipulation.

Now, MIT physicists have observed the elusive fractional charge effect, this time in a simpler material: five layers of graphene an atom-thin layer of carbon that stems from graphite and common pencil lead. They report their results on February 21 in the journal Nature.

A photo of the team. From left to right: Long Ju, Postdoc Zhengguang Lu, visiting undergraduate Yuxuan Yao, graduate student Tonghang Hang. Credit: Jixiang Yang

They found that when five sheets of graphene are stacked like steps on a staircase, the resulting structure inherently provides just the right conditions for electrons to pass through as fractions of their total charge, with no need for any external magnetic field.

The results are the first evidence of the fractional quantum anomalous Hall effect (the term anomalous refers to the absence of a magnetic field) in crystalline graphene, a material that physicists did not expect to exhibit this effect.

This five-layer graphene is a material system where many good surprises happen, says study author Long Ju, assistant professor of physics at MIT. Fractional charge is just so exotic, and now we can realize this effect with a much simpler system and without a magnetic field. That in itself is important for fundamental physics. And it could enable the possibility for a type of quantum computing that is more robust against perturbation.

Jus MIT co-authors are lead author Zhengguang Lu, Tonghang Han, Yuxuan Yao, Aidan Reddy, Jixiang Yang, Junseok Seo, and Liang Fu, along with Kenji Watanabe and Takashi Taniguchi at the National Institute for Materials Science in Japan.

The fractional quantum Hall effect is an example of the weird phenomena that can arise when particles shift from behaving as individual units to acting together as a whole. This collective correlated behavior emerges in special states, for instance when electrons are slowed from their normally frenetic pace to a crawl that enables the particles to sense each other and interact. These interactions can produce rare electronic states, such as the seemingly unorthodox splitting of an electrons charge.

In 1982, scientists discovered the fractional quantum Hall effect in heterostructures of gallium arsenide, where a gas of electrons confined in a two-dimensional plane is placed under high magnetic fields. The discovery later won the group a Nobel Prize in Physics.

[The discovery] was a very big deal, because these unit charges interacting in a way to give something like fractional charge was very, very bizarre, Ju says. At the time, there were no theory predictions, and the experiments surprised everyone.

Those researchers achieved their groundbreaking results using magnetic fields to slow down the materials electrons enough for them to interact. The fields they worked with were about 10 times stronger than what typically powers an MRI machine.

In August 2023, scientists at the University of Washington reported the first evidence of fractional charge without a magnetic field. They observed this anomalous version of the effect, in a twisted semiconductor called molybdenum ditelluride. The group prepared the material in a specific configuration, which theorists predicted would give the material an inherent magnetic field, enough to encourage electrons to fractionalize without any external magnetic control.

The no magnets result opened a promising route to topological quantum computing a more secure form of quantum computing, in which the added ingredient of topology (a property that remains unchanged in the face of weak deformation or disturbance) gives a qubit added protection when carrying out a computation. This computation scheme is based on a combination of fractional quantum Hall effect and a superconductor. It used to be almost impossible to realize: One needs a strong magnetic field to get fractional charge, while the same magnetic field will usually kill the superconductor. In this case the fractional charges would serve as a qubit (the basic unit of a quantum computer).

That same month, Ju and his team happened to also observe signs of anomalous fractional charge in graphene a material for which there had been no predictions for exhibiting such an effect.

Jus group has been exploring electronic behavior in graphene, which by itself has exhibited exceptional properties. Most recently, Jus group has looked into pentalayer graphene a structure of five graphene sheets, each stacked slightly off from the other, like steps on a staircase. Such pentalayer graphene structure is embedded in graphite and can be obtained by exfoliation using Scotch tape. When placed in a refrigerator at ultracold temperatures, the structures electrons slow to a crawl and interact in ways they normally wouldnt when whizzing around at higher temperatures.

In their new work, the researchers did some calculations and found that electrons might interact with each other even more strongly if the pentalayer structure were aligned with hexagonal boron nitride (hBN) a material that has a similar atomic structure to that of graphene, but with slightly different dimensions. In combination, the two materials should produce a moir superlattice an intricate, scaffold-like atomic structure that could slow electrons down in ways that mimic a magnetic field.

We did these calculations, then thought, lets go for it, says Ju, who happened to install a new dilution refrigerator in his MIT lab last summer, which the team planned to use to cool materials down to ultralow temperatures, to study exotic electronic behavior.

The researchers fabricated two samples of the hybrid graphene structure by first exfoliating graphene layers from a block of graphite, then using optical tools to identify five-layered flakes in the steplike configuration. They then stamped the graphene flake onto an hBN flake and placed a second hBN flake over the graphene structure. Finally, they attached electrodes to the structure and placed it in the refrigerator, set to near absolute zero.

As they applied a current to the material and measured the voltage output, they started to see signatures of fractional charge, where the voltage equals the current multiplied by a fractional number and some fundamental physics constants.

The day we saw it, we didnt recognize it at first, says first author Lu. Then we started to shout as we realized, this was really big. It was a completely surprising moment.

This was probably the first serious samples we put in the new fridge, adds co-first author Han. Once we calmed down, we looked in detail to make sure that what we were seeing was real.

With further analysis, the team confirmed that the graphene structure indeed exhibited the fractional quantum anomalous Hall effect. It is the first time the effect has been seen in graphene.

Graphene can also be a superconductor, Ju says. So, you could have two totally different effects in the same material, right next to each other. If you use graphene to talk to graphene, it avoids a lot of unwanted effects when bridging graphene with other materials.

For now, the group is continuing to explore multilayer graphene for other rare electronic states.

We are diving in to explore many fundamental physics ideas and applications, he says. We know there will be more to come.

Reference: Fractional quantum anomalous Hall effect in multilayer graphene by Zhengguang Lu, Tonghang Han, Yuxuan Yao, Aidan P. Reddy, Jixiang Yang, Junseok Seo, Kenji Watanabe, Takashi Taniguchi, Liang Fu and Long Ju, 21 February 2024, Nature. DOI: 10.1038/s41586-023-07010-7

This research is supported in part by the Sloan Foundation, and the National Science Foundation.

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Fractional Electrons: MIT's New Graphene Breakthrough Is Shaping the Future of Quantum Computing - SciTechDaily

Scientists have created an error-free quantum bit, or qubit, from a single pulse of light, raising hopes for a light-based room-temperature quantum computer in the future.

While bits in classical computers store information as either 1 or 0, qubits in quantum computers can encode information as a superposition of 1 and 0, meaning one qubit can adopt both states simultaneously.

When quantum computers have millions of qubits in the future, they will process calculations in a fraction of the time that today's most powerful supercomputers can. But the most powerful quantum computers so far have only been built with roughly 1,000 qubits.

Most qubits are made from a superconducting metal, but these need to be cooled to near absolute zero to achieve stability for the laws of quantum mechanics to dominate. Qubits are also highly prone to failure, and if a qubit fails during a computation, the data it stores is lost, and a calculation is delayed.

One way to solve this problem is to stitch multiple qubits together using quantum entanglement, an effect Albert Einstein famously referred to as "spooky action at a distance. By connecting them intrinsically through space and time so they share a single quantum state, scientists can form one "logical qubit," storing the same information in all of the constituent physical qubits. If one or more physical qubits fails, the calculation can continue because the information is stored elsewhere.

Related: How could this new type of room-temperature qubit usher in the next phase of quantum computing?

But you need many physical qubits to create one logical qubit. Quantum computing company QuEra and researchers at Harvard, for example, recently demonstrated a breakthrough in quantum error correction using logical qubits, publishing their findings Dec. 6, 2023, in the journal Nature. This will lead to the launch of a quantum computer with 10 logical qubits later this year but it will be made using 256 physical qubits.

For that reason, researchers are looking at alternative ways to create qubits and have previously demonstrated that you can create a physical qubit from a single photon (particle of light). This can also operate at room temperature because it doesn't rely on the conventional way to make qubits, using superconducting metals that need to be cooled. But single physical photonic qubits are still prone to failure.

In a study published in August 2023 in the journal Nature, scientists showed that you can successfully entangle multiple photonic qubits. Building on this research, the same team has now demonstrated that you can create a de facto logical qubit which has an inherent capacity for error correction using a single laser pulse that contains multiple photons entangled by nature. They published their findings Jan. 18 in the journal Science.

"Our laser pulse was converted to a quantum optical state that gives us an inherent capacity to correct errors," Peter van Loock, a professor of theoretical quantum optics at Johannes Gutenberg University of Mainz in Germany and co-author of the Dec. 6 study, said in a statement. "Although the system consists only of a laser pulse and is thus very small, it can in principle eradicate errors immediately."

Based on their results, there's no need to create individual photons as qubits from different light pulses and entangle them afterward. You would need just one light pulse to create a "robust logical qubit," van Loock added.

Although the results are promising, the logical qubit they created experimentally wasn't good enough to achieve the error-correction levels needed to perform as a logical qubit in a real quantum computer. Rather, the scientists said this work shows you can transform a non-correctable qubit into a correctable qubit using photonic methods.

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Qubits are notoriously prone to failure but building them from a single laser pulse may change this - Livescience.com

A new phase of matter previously recognized only in theory has been created by researchers using a quantum processor, which demonstrates the control of an exotic form of particles called non-Abelian anyons.

Neither fermions nor bosons, these exotic anyons fall someplace in between and are believed only to be able to exist in two-dimensional systems. Controlling them allowed the creation of an entirely new phase of matter the researchers now call non-Abelian topological order.

In our everyday world of three dimensions, just two types of particles exist: bosons and fermions. Bosons include light, as well as the subatomic particle known as the Higgs boson, whereas fermions comprise protons, neutrons, and electrons that constitute the matter throughout our universe.

Non-Abelian anyons are identified as quasiparticles, meaning that they are particle-like manifestations of excitation that persist for periods within a specific state of matter. They are of particular interest for their ability to store memory, which may have a variety of technological applications, particularly in quantum computing.

One of the reasons for this is because of the stability non-Abelian anyons possess when compared to qubits, which are currently used in quantum computing platforms. Unlike qubits, which can at times be less than reliable, non-Abelian anyons can store information as they move around one another without the influence of their environment, making them ideal targets for use in computational systems once they can be harnessed at larger scales.

In recent research, Ashvin Vishwanath, the George Vasmer Leverett Professor of Physics at Harvard University, used a quantum processor to test how non-Abelian anyons might be leveraged to perform quantum computation.

One very promising route to stable quantum computing is to use these kinds of exotic states of matter as the effective quantum bits and to do quantum computation with them, said Nat Tantivasadakarn, a former Harvard student now at Caltech, who participated in the research.

To achieve this unique and exotic state of matter, the team devised an experiment that, in principle, was simple: they decided to push the capabilities of Quantinuums newest H2 processor to its limits.

Beginning with 27 trapped ions, the team employed a series of partial measurements designed to follow a sequence in which their complexity increased within the quantum system, which would result in a quantum wave function possessing the characteristics of the particular particles they hoped to generate.

Vishwanath likened their efforts to sculpting a specific state through the process of measurement, a component of the research process that has led physicists in the past to greatand at times perplexingdiscoveries.

Measurement is the most mysterious aspect of quantum mechanics, Vishwanath said, leading to famous paradoxes like Schrdingers cat and numerous philosophical debates.

Employing an adaptive circuit on Quantinuums H2 trapped-ion quantum processor, Vishwanath and his team were successfully able to drive the processor to its limits, allowing them to create and move anyons along what are known as Borromean rings, used in mathematics to describe a trio of closed curves in three-dimensional space that are linked topologically, and are unable to be separated.

Under such conditions, non-Abelian anyons tunneled around a torus created all 22 ground states, as well as an excited state with a single anyona peculiar feature of non-Abelian topological order, the team writes in a newly published study.

This work illustrates the counterintuitive nature of non-Abelions and enables their study in quantum devices, they conclude.

At least for me, it was just amazing that it all works, and that we can do something very concrete, Vishwanath recently told the Harvard Gazette.

It really connects many different aspects of physics over the years, from foundational quantum mechanics to more recent ideas of these new kinds of particles.

Vishwanath, Tantivasadakarn, and their colleague Ruben Verresen were all co-authors on the teams new paper, Non-Abelian topological order and anyons on a trapped-ion processor, which appeared in the journal Nature on February 14, 2024.

Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. He can be reached by email atmicah@thedebrief.org. Follow his work atmicahhanks.comand on X:@MicahHanks.

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New Phase of Matter Created During Experiments with Exotic Particles in Quantum Processor - The Debrief

Apples security team claims to have achieved a breakthrough that advances the state of the art of end-to-end messaging. With the upcoming release of iOS 17.4, iPadOS 17.4, macOS 14.4, and watchOS 10.4, the company is bringing a new cryptographic protocol called PQ3 to iMessage that it purports to offer even more robust encryption and defenses against sophisticated quantum computing attacks.

Such attacks arent yet a broad threat today, but Apple is preparing for a future where bad actors try to unwind current encryption standards and iMessages security layers with the help of massively powerful computers. Such scenarios could start playing out by the end of the decade, but experts agree that the tech industry need to start defending against them well in advance.

PQ3 is the first messaging protocol to reach what we call Level 3 security providing protocol protections that surpass those in all other widely deployed messaging apps, the security team wrote. Yes, Apple came up with its own ranking system for messaging service security, and iMessage now stands alone at the top thanks to these latest PQ3 advancements.

In the companys view, theyre enough to put Apples service above Signal, which itself recently rolled out more sophisticated security defenses. (For reference, the current version of iMessage ranks as level 1 alongside WhatsApp, Viber, Line, and the older version of Signal.) More than simply replacing an existing algorithm with a new one, we rebuilt the iMessage cryptographic protocol from the ground up to advance the state of the art in end-to-end encryption, Apple wrote.

Apple says that hackers can stow away any encrypted data they obtain today in hopes of being able to break through in several years once quantum computers become a realistic attack vector:

Although quantum computers with this capability dont exist yet, extremely well-resourced attackers can already prepare for their possible arrival by taking advantage of the steep decrease in modern data storage costs. The premise is simple: such attackers can collect large amounts of todays encrypted data and file it all away for future reference. Even though they cant decrypt any of this data today, they can retain it until they acquire a quantum computer that can decrypt it in the future, an attack scenario known asHarvest Now, Decrypt Later.

You can read all the nitty-gritty details on PQ3 in Apples blog post, which is a great example of the companys focus on protecting user data. And as weve learned in recent months, Apple wont hesitate to shut out third parties even those with well-meaning intentions that attempt to encroach on its iPhone-selling messaging platform in any way.

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Apple is already defending iMessage against tomorrow's quantum computing attacks - The Verge

TORONTO, Feb. 23, 2024 Xanadu, a world leader in photonic quantum computing, received a repayable contribution from the Government of Canada, through the Federal Economic Development Agency for Southern Ontario (FedDev Ontario), to help companies advance and commercialize their quantum products.

This funding, through the Regional Quantum Initiative (RQI), will accelerate the development of PennyLane, Xanadus open-source, cloud-based software framework for quantum machine learning, quantum chemistry, and quantum computing.

Southern Ontario is well-positioned for quantum breakthroughs because we are home to world-leading research centers and high-potential quantum companies, like the ones we are celebrating today. Businesses in this sector are creating incredible technologies and our government is providing support so they can bring them to market faster, advancing Canadas role as a world leader in quantum technologies, said the Hon. Filomena Tassi, Minister responsible for the Federal Economic Development Agency for Southern Ontario.

With todays announcement, our government is strengthening Canadas position in quantum technology and helping to boost economic growth and create good jobs for Canadians. Through these investments, we will continue to build this sector and support made-in-Canada technologies that will have a major impact on industries like computing, communications, security and health care, said Bryan May, Parliamentary Secretary to the Minister for Small Business and to the Minister responsible for FedDev Ontario.

Viable applications of quantum computers are contingent upon achieving fault-tolerant quantum computation (FTQC). Great strides have been made in the field, and to continue the development of quantum computing technologies and ensure FTQC is achieved, the future quantum workforce must be well-trained.

Since 2016, Xanadu has been on a mission to make quantum computers useful and available to people everywhere. One key for that mission is accessibility to top-tier quantum education that will help build the future quantum workforce. To support this goal, Xanadu has worked with numerous universities across Canada and the world to create custom educational programs and has established a dedicated quantum community team that runs educational events, creates free educational materials, and engages directly with the community.

As a budget commitment in 2021, the Government of Canada launched its National Quantum Strategy in January 2023, which is underpinned by three pillars: research, talent, and commercialization. FedDev Ontario is one of the regional development agencies focused on supporting high-potential quantum projects and scaling promising Canadian companies.

Through RQI, Xanadu is receiving a repayable investment of $3.75 million to accelerate its core quantum software, PennyLane. This funding will create 22 new quantum jobs, further strengthening Canadas quantum workforce. The objectives of this project include advancing the operating infrastructure to provide a broader cloud offering, as well as increasing community support and creating more user engagement materials.

We are thrilled to receive this FedDev Ontario support to advance our quantum technology, build a larger quantum community, and further strengthen Canadas position as a global quantum leader, said Christian Weedbrook, Xanadu Founder and CEO.

About Xanadu

Xanadu is a quantum computing company with the mission to build quantum computers that are useful and available to people everywhere. Founded in 2016, Xanadu has become one of the worlds leading quantum hardware and software companies. The company also leads the development of PennyLane, an open-source software library for quantum computing and application development.

Source: Xanadu

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Government of Canada Supports Xanadu to Accelerate Quantum Computing Research and Education - HPCwire

While artificial intelligence and semiconductors capture global attention, some U.S. policymakers want to ensure Congress doesn't fail to invest and stay competitive in other emerging technologies, including quantum computing.

Quantum computing regularly lands on the U.S. critical and emerging technologies list, which pinpoints technologies that could affect U.S. national security. Quantum computing -- an area of computer science that uses quantum physics to solve problems too complex for traditional computers -- not only affects U.S. national security, but intersects with other prominent technologies and industries, including AI, healthcare and communications.

The U.S. first funded quantum computing research and development in 2018 through the $1.2 billion National Quantum Initiative Act. It's something policymakers now want to continue through the National Quantum Initiative Reauthorization Act. Reps. Frank Lucas (R-Okla.) and Zoe Lofgren (D-Calif.) introduced the legislation in November 2023, and it has yet to pass the House despite having bipartisan support.

Continuing to invest in quantum computing R&D means staying competitive with other countries making similar investments to not only stay ahead of the latest advancements, but protect national security, said Isabel Al-Dhahir, principal analyst at GlobalData.

"Quantum computing's geopolitical weight and the risk a powerful quantum computer poses to current cybersecurity measures mean that not only the U.S., but also China, the EU, the U.K., India, Canada, Japan and Australia are investing heavily in the technology and are focused on building strong internal quantum ecosystems in the name of national security," she said.

Global competition in quantum computing will increase as the technology moves from theoretical to practical applications, Al-Dhahir said. Quantum computing has the potential to revolutionize areas such as drug development and cryptography.

Al-Dhahir said while China is investing $15 billion over the next five years in its quantum computing capabilities, the EU's Quantum Technologies Flagship program will provide $1.2 billion in funding over the next 10 years. To stay competitive, the U.S. needs to continue funding quantum computing R&D and studying practical applications for the technology.

"If reauthorization fails, it will damage the U.S.'s position in the global quantum race," she said.

Lofgren, who spoke during The Intersect: A Tech and Policy Summit earlier this month, said it's important to pass the National Quantum Initiative Reauthorization Act to "maintain our competitive edge." The legislation aims to move beyond scientific research and into practical applications of quantum computing, along with ensuring scientists have the necessary resources to accomplish those goals, she said.

Indeed, Sen. Marsha Blackburn (R-Tenn.) said during the summit that the National Quantum Initiative Act needs to be reauthorized for the U.S. to move forward. Blackburn, along with Sen. Ben Ray Lujn (D-N.M.), has also introduced the Quantum Sandbox for Near-Term Applications Act to advance commercialization of quantum computing.

The 2018 National Quantum Initiative Act served a "monumental" purpose in mandating agencies such as the National Science Foundation, NIST and the Department of Energy to study quantum computing and create a national strategy, said Joseph Keller, a visiting fellow at the Brookings Institution.

Though the private sector has made significant investments in quantum computing, Keller said the U.S. would not be a leader in quantum computing research without federal support, especially with goals to eventually commercialize the technology at scale. He said that's why it's pivotal for the U.S. to pass the National Quantum Initiative Reauthorization Act, even amid other congressional priorities such as AI.

"I don't think you see any progress forward without the passage of that legislation," Keller said.

Despite investment from numerous big tech companies, including Microsoft, Intel, IBM and Google, significant technical hurdles remain for the broad commercialization of quantum computing, Al-Dhahir said.

She said the quantum computing market faces issues such as overcoming high error rates -- for example, suppressing error rates requires "substantially higher" qubit counts than what is being achieved today. A qubit, short for quantum bit, is considered a basic unit of information in quantum computing.

IBM released the first quantum computer with more than 1,000 qubits in 2023. However, Al-Dhahir said more is needed to avoid high error rates in quantum computing.

"The consensus is that hundreds of thousands to millions of qubits are required for practical large-scale quantum computers," she said.

Indeed, industry is still trying to identify the economic proposition of quantum computing, and the government has a role to play in that, Brookings' Keller said.

"It doesn't really have these real-world applications, things you can hold and touch," he said. "But there are breakthroughs happening in science and industry."

Lofgren said she recognizes that quantum computing has yet to reach the stage of practical, commercial applications, but she hopes that legislation such as the National Quantum Initiative Reauthorization Act will help the U.S. advance quantum computing to that stage.

"Quantum computing is not quite there yet, although we are making tremendous strides," she said.

Makenzie Holland is a news writer covering big tech and federal regulation. Prior to joining TechTarget Editorial, she was a general reporter for the Wilmington StarNews and a crime and education reporter at the Wabash Plain Dealer.

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U.S. weighs National Quantum Initiative Reauthorization Act - TechTarget

A radical superconducting qubit design promises to extend their runtime by addressing decoherence challenges in quantum computing.

A new qubit design based on superconductors could revolutionize quantum computing. By leveraging the distinct properties of single-atom-thick layers of materials, this new approach to superconducting circuits promises to significantly extend the runtime of a quantum computer, addressing a major challenge in the field.

This limitation on continuous operation time arises because the quantum state of a qubit the basic computing unit of a quantum computer can be easily destabilized due to interactions with its environment and other qubits. This destruction of the quantum state is called decoherence and leads to errors in computations.

Among the various types of qubits that scientists have created, including photons, trapped ions, and quantum dots, superconducting qubits are desirable because they can switch between different states in the shortest amount of time.

Their operation is based on the fact that, due to subtle quantum effects, the power of the electric current flowing through the superconductor can take discrete values, each corresponding to a state of 0 and/or 1 (or even larger values for some designs).

For superconducting qubits to work correctly, they require the presence of a gap in the superconducting circuit called a Josephson junction through which an electrical current flows through a quantum phenomenon called tunneling the passage of particles through a barrier that, according to the laws of classical physics, they should not be able to cross.

The problem is, the advantage of superconducting qubits in enhanced switching time comes at a cost: They are more susceptible to decoherence, which occurs in milliseconds, or even faster. To mitigate this issue, scientists typically resort to meticulous adjustments of circuit configurations and qubit placements with few net gains.

Addressing this challenge with a more radical approach, an international team of researchers proposed a novel Josephson junction design using two, single-atom-thick flakes of a superconducting copper-based material called a cuprate. They called their design flowermon.

In their study published in the Physical Review Letters, the team applied the fundamental laws of quantum mechanics to analyze the current flow through a Josephson junction and discovered that if the angle between the crystal lattices of two superconducting cuprate sheets is 45 degrees, the qubit exhibits more resilience to external disturbances compared to conventional designs based on materials like niobium and tantalum.

The flowermon modernizes the old idea of using unconventional superconductors for protected quantum circuits and combines it with new fabrication techniques and a new understanding of superconducting circuit coherence, Uri Vool, a physicist at the Max Planck Institute for Chemical Physics of Solids in Germany, explained in a press release.

The teams calculations suggest that the noise reduction promised by their design could increase the qubits coherence time by orders of magnitude, thereby enhancing the continuous operation of quantum computers. However, they view their research as just the beginning, envisioning future endeavors to further optimize superconducting qubits based on their findings.

The idea behind the flowermon can be extended in several directions: Searching for different superconductors or junctions yielding similar effects, exploring the possibility to realize novel quantum devices based on the flowermon, said Valentina Brosco, a researcher at the Institute for Complex Systems Consiglio Nazionale delle Ricerche and Physics Department University of Rome. These devices would combine the benefits of quantum materials and coherent quantum circuits or using the flowermon or related design to investigate the physics of complex superconducting heterostructures.

This is only the first simple concrete example of utilizing the inherent properties of a material to make a new quantum device, and we hope to build on it and find additional examples, eventually establishing a field of research that combines complex material physics with quantum devices, Vool added.

Since the teams study was purely theoretical, even the simplest heterostructure-based qubit design they proposed requires experimental validation a step that is currently underway.

Experimentally, there is still quite a lot of work towards implementing this proposal, concluded Vool. We are currently fabricating and measuring hybrid superconducting circuits which integrate these van der Waals superconductors, and hope to utilize these circuits to better understand the material, and eventually design and measure protected hybrid superconducting circuits to make them into real useful devices.

Reference: Uri Vool, et al., Superconducting Qubit Based on Twisted Cuprate Van der Waals Heterostructures, Physical Review Letters (2024). DOI: 10.1103/PhysRevLett.132.017003

Feature image credit: SuttleMedia on Pixabay

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Superconducting qubit promises breakthrough in quantum computing - Advanced Science News

Researchers at Penn State have introduced a groundbreaking material fusion that enables a new form of superconductivity, crucial for advancing quantum computing and exploring the theoretical chiral Majorana particles. Their study demonstrates how combining magnetic materials can lead to emergent superconductivity, marking a significant leap in creating chiral topological superconductors and potentially unlocking new avenues in quantum computing research.

A new fusion of materials, each with special electrical properties, has all the components required for a unique type of superconductivity that could provide the basis for more robust quantum computing. The new combination of materials, created by a team led by researchers at Penn State, could also provide a platform to explore physical behaviors similar to those of mysterious, theoretical particles known as chiral Majoranas, which could be another promising component for quantum computing.

The new study was recently published in the journal Science. The work describes how the researchers combined the two magnetic materials in what they called a critical step toward realizing the emergent interfacial superconductivity, which they are currently working toward.

Superconductors materials with no electrical resistance are widely used in digital circuits, the powerful magnets in magnetic resonance imaging (MRI) and particle accelerators, and other technology where maximizing the flow of electricity is crucial. When superconductors are combined with materials called magnetic topological insulators thin films only a few atoms thick that have been made magnetic and restrict the movement of electrons to their edges the novel electrical properties of each component work together to produce chiral topological superconductors. The topology, or specialized geometries and symmetries of matter, generates unique electrical phenomena in the superconductor, which could facilitate the construction of topological quantum computers.

Quantum computers have the potential to perform complex calculations in a fraction of the time it takes traditional computers because, unlike traditional computers which store data as a one or a zero, the quantum bits of quantum computers store data simultaneously in a range of possible states. Topological quantum computers further improve upon quantum computing by taking advantage of how electrical properties are organized to make the computers robust to decoherence, or the loss of information that happens when a quantum system is not perfectly isolated.

Creating chiral topological superconductors is an important step toward topological quantum computation that could be scaled up for broad use, said Cui-Zu Chang, Henry W. Knerr Early Career Professor and associate professor of physics at Penn State and co-corresponding author of the paper. Chiral topological superconductivity requires three ingredients: superconductivity, ferromagnetism, and a property called topological order. In this study, we produced a system with all three of these properties.

The researchers used a technique called molecular beam epitaxy to stack together a topological insulator that has been made magnetic and an iron chalcogenide (FeTe), a promising transition metal for harnessing superconductivity. The topological insulator is a ferromagnet a type of magnet whose electrons spin the same way while FeTe is an antiferromagnet, whose electrons spin in alternating directions. The researchers used a variety of imaging techniques and other methods to characterize the structure and electrical properties of the resulting combined material and confirmed the presence of all three critical components of chiral topological superconductivity at the interface between the materials.

Prior work in the field has focused on combining superconductors and nonmagnetic topological insulators. According to the researchers, adding in the ferromagnet has been particularly challenging.

Normally, superconductivity and ferromagnetism compete with each other, so it is rare to find robust superconductivity in a ferromagnetic material system, said Chao-Xing Liu, professor of physics at Penn State and co-corresponding author of the paper. But the superconductivity in this system is actually very robust against the ferromagnetism. You would need a very strong magnetic field to remove the superconductivity.

The research team is still exploring why superconductivity and ferromagnetism coexist in this system.

Its actually quite interesting because we have two magnetic materials that are non-superconducting, but we put them together and the interface between these two compounds produces very robust superconductivity, Chang said. Iron chalcogenide is antiferromagnetic, and we anticipate its antiferromagnetic property is weakened around the interface to give rise to the emergent superconductivity, but we need more experiments and theoretical work to verify if this is true and to clarify the superconducting mechanism.

The researchers said they believe this system will be useful in the search for material systems that exhibit similar behaviors as Majorana particles theoretical subatomic particles first hypothesized in 1937. Majorana particles act as their own antiparticle, a unique property that could potentially allow them to be used as quantum bits in quantum computers.

Providing experimental evidence for the existence of chiral Majorana will be a critical step in the creation of a topological quantum computer, Chang said. Our field has had a rocky past in trying to find these elusive particles, but we think this is a promising platform for exploring Majorana physics.

Reference: Interface-induced superconductivity in magnetic topological insulators by Hemian Yi, Yi-Fan Zhao, Ying-Ting Chan, Jiaqi Cai, Ruobing Mei, Xianxin Wu, Zi-Jie Yan, Ling-Jie Zhou, Ruoxi Zhang, Zihao Wang, Stephen Paolini, Run Xiao, Ke Wang, Anthony R. Richardella, John Singleton, Laurel E. Winter, Thomas Prokscha, Zaher Salman, Andreas Suter, Purnima P. Balakrishnan, Alexander J. Grutter, Moses H. W. Chan, Nitin Samarth, Xiaodong Xu, Weida Wu, Chao-Xing Liu and Cui-Zu Chang, 8 February 2024, Science. DOI: 10.1126/science.adk1270

In addition to Chang and Liu, the research team at Penn State at the time of the research included postdoctoral researcher Hemian Yi; graduate students Yi-Fan Zhao, Ruobing Mei, Zi-Jie Yan, Ling-Jie Zhou, Ruoxi Zhang, Zihao Wang, Stephen Paolini and Run Xiao; assistant research professors in the Materials Research Institute Ke Wang and Anthony Richardella; Evan Pugh University Professor Emeritus of Physics Moses Chan; and Verne M. Willaman Professor of Physics and Professor of Materials Science and Engineering Nitin Samarth. The research team also includes Ying-Ting Chan and Weida Wu at Rutgers University; Jiaqi Cai and Xiaodong Xu at the University of Washington; Xianxin Wu at the Chinese Academy of Sciences; John Singleton and Laurel Winter at the National High Magnetic Field Laboratory; Purnima Balakrishnan and Alexander Grutter at the National Institute of Standards and Technology; and Thomas Prokscha, Zaher Salman, and Andreas Suter at the Paul Scherrer Institute of Switzerland.

This research is supported by the U.S. Department of Energy. Additional support was provided by the U.S. National Science Foundation (NSF), the NSF-funded Materials Research Science and Engineering Center for Nanoscale Science at Penn State, the Army Research Office, the Air Force Office of Scientific Research, the state of Florida and the Gordon and Betty Moore Foundations EPiQS Initiative.

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Quantum Computing Breakthrough: New Fusion of Materials Has All the Components Required for a Unique Type of ... - SciTechDaily

The race for quantum computing dominance is on.

In fact,according to SDXCentral.com, the U.S. and China are neck and neck at the moment. The U.S. has already committed $3 billion in funding for quantum computing, with another $12 billion coming from the National Quantum Computing Initiative. China is committing about $15 billion over the next five years. This is all great news for quantum computing stocks.

Even the U.K., Canada, Israel, Australia, Japan, and the European Union are jumping into the quantum computing market. As the race picks up, the quantum computing market could grow from $928.8 million this year to more than $6.5 billion by 2030,as noted by Fortune Business Insights.

All of this could be a substantial catalyst for the following quantum computing stocks.

Source: Amin Van / Shutterstock.com

Earlier this month, IonQ (NYSE:IONQ), trading at $10.27, was highlighted.

While its up slightly at $10.87, give this one a good deal of patience. On Feb. 1, the company just boosted itsfull-year revenue guidanceto a range of $21.2 million to $22 million from its prior range of $18.9 million to $19.3 million. It also boosted its full-year bookings to a new range of $60 million to $63 million from a prior range of $49 million to $56 million.

Quantum computing has the potential to be a game changer it can help us create new drugs and fight disease, turbocharge clean energy alternatives, and improve food production,according toWashington State U.S. Senator Maria Cantwell, as quoted in a IONQ press release.

Further, IonQ just opened its firstquantum computing manufacturing facility in Washington.

The company inaugurated the first U.S.-based factory producing replicable quantum computers for client data centers, enhancing technology innovation and manufacturing in the Pacific Northwest. CEO Peter Chapman highlighted IonQs commitment to commercializing quantum computing,added Investorplace contributor Chris MacDonald.

Source: T. Schneider / Shutterstock

Recently reported, D-Wave Quantum(NYSE:QBTS) traded at 85 cents. Yet, after hitting a high of $2.08 on Feb. 15, its now back to $1.74 and is still a strong opportunity.

Forcing QBTS higher, the company said its1,200+ qubit Advantage2 prototypewas now available. Also, it partnered with industrialgenerative AI company Zapata AI. It will develop and market commercial applications, combining the power of generative AI and quantum computing technologies.In addition, it just announced that it andNEC Australiaare teaming to release two new quantum services in the Australian market.

Source: Bartlomiej K. Wroblewski / Shutterstock.com

Recently, Rigetti Computing(NASDAQ:RGTI) popped from about $1.20 to $1.69 a share on heavy volume. For example, last Friday, volume spiked to 19.24 million, as compared to daily average volume of 3.86 million shares.

Further, the company wasawarded a Small Business Research Initiative (SBRI)grantfrom Innovate UK and funded by the National Quantum Computing Centre(NQCC) to develop and deliver a quantum computer to the NQCC.

The proposed system will feature the hallmarks of Rigettis recently launched 84-qubit Ankaa-2 system, including tunable couplers and a square lattice, as noted in a company press release. This new chip architecture enables faster gate times, higher fidelity, and greater connectivity compared to Rigettis previous generations of quantum processing units (QPUs).

On the date of publication, Ian Cooper did not hold (either directly or indirectly) any positions in the securities mentioned. The opinions expressed in this article are those of the writer, subject to the InvestorPlace.comPublishing Guidelines.

Ian Cooper, a contributor to InvestorPlace.com, has been analyzing stocks and options for web-based advisories since 1999.

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3 Quantum Computing Stocks That Could Be Multibaggers in the Making: February Edition - InvestorPlace

Over the years, several players have emerged in the quantum computing market, offering a variety of approaches to the technology.

From trapped ions to photonic or superconducting, these systems all show promise and all face significant challenges to becoming commercially viable.

In this Zero Downtime podcast episode, we are joined by Yuval Boger of QuEra, a neutral atom-based quantum computer company, to talk about the different types of quantum computers and the challenges in making them powerful and accurate enough for widespread adoption and deployment.

In addition, we talk about some of the uses that quantum computing may be more appropriate than traditional supercomputing.

We also discuss some of the practicalities of deploying quantum computers in data centers, with some such systems requiring powerful cooling systems.

So, which type of quantum computer will win out in the end?

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DCD Podcast - The fundamentals of quantum computing, with Yuval Boger, QuEra - DCD - DatacenterDynamics