Tag Archives: quantum computing

Scientists Discover Hidden Superconducting Patterns Inside Diamond

Posted on by
Reply

Diamond’s importance in science extends far beyond its brilliance and luxury appeal. Researchers value the material for its exceptional hardness, remarkable ability to conduct heat, and transparency across much of the light spectrum. About 20 years ago, scientists uncovered another surprising property: under specific conditions, diamond can behave as a superconductor, allowing electrical current to move without resistance.

For years, however, researchers struggled to understand the physics behind this phenomenon, limiting efforts to use superconducting diamond in advanced technologies.

Now, scientists from Pennsylvania State University, the University of Chicago Pritzker School of Molecular Engineering and the U.S. Department of Energy-backed Q-NEXT, led by Argonne National Laboratory, say they have uncovered crucial clues explaining how superconductivity emerges inside diamond.

By engineering ultra-high-quality diamond structures and separating genuine electronic signals from background material noise, the team was able to reveal mechanisms that had remained hidden for decades.

The findings, published in the Proceedings of the National Academy of Sciences, could open the door to multifunction quantum chips capable of combining several quantum technologies within a single platform.

Researchers believe the breakthrough could help bridge one of quantum computing’s biggest challenges — connecting different types of qubits, or quantum bits, that often struggle to work together efficiently. Diamond, they say, may provide a rare material platform capable of supporting multiple quantum functions simultaneously while remaining thermally efficient and compatible with existing electronics.

“This offers a new way of thinking by integrating superconducting and semiconductor behavior to create opportunities for multifunction quantum devices,” said David Awschalom, professor of Quantum Science and Engineering and Physics at UChicago PME and director of the Chicago Quantum Exchange.

Awschalom said future technologies could potentially combine light, spin, superconductivity and magnetism within a single engineered material that also integrates with modern microelectronics.

“There’s enormous potential at the interface between these nominally disparate areas of science,” he said, adding that deeper atomic-scale engineering could unlock entirely new classes of quantum systems.

How it works

In order to become superconducting, diamond must be “doped” with atoms of boron. (Doping is the process of adding different atoms to a host material to control or change certain properties, such as electrical conductivity).

In the study, the scientists used a facility at Penn State’s Applied Research Lab to synthesize extremely high-quality diamond thin films doped with a random distribution of boron. Surprisingly, the research team found hidden order within this disordered distribution of boron in the form of a mosaic of superconducting “puddles” that must eventually link up to allow electricity to flow without resistance – which they describe as “granular superconductivity”. These puddles might form due to clustering of boron atoms within diamond, however even in microscopically uniform films, the superconductivity was found to be granular. More importantly, the superconducting mosaic is seemingly tunable and can be stretched and skewed by changing the magnetic field, electrical current and temperature.

“The graduate student leading the project discovered complex patterns in the electrical behavior of the films that could only be explained by intrinsic granularity,” said Nitin Samarth, Verne M. Willaman Professor of Physics and Materials Science and Engineering at Penn State and co-corresponding author of the paper. “This serendipitous discovery caught us totally by surprise because these are structurally homogeneous, crystalline films! So, the question was: where is this granularity coming from?”

By identifying how electrons move through and between these superconducting puddles, scientists can now begin to “stitch” these superconducting puddles together more effectively, which could significantly boost the performance and temperature range of future quantum devices. Currently, these systems require extreme cooling to function; raising that temperature would make quantum technology more accessible and energy-efficient.

Potential for new innovations

One of the most exciting implications of this research, says Awschalom, is the potential for multifunctional ‘quantum-on-chip’ applications, where multiple different types of quantum information technologies—like quantum communication and quantum computing—could coexist and work together on a single diamond chip. This is due to diamond’s built-in “spin-photon interface,” meaning it naturally connects light to matter without any other technology necessary.

As the quantum industry looks to develop a domestic diamond supply chain, this “all-in-one” diamond platform offers a path toward chips that are not only more powerful but also easier to integrate with the classical high-frequency electronics we use today.

These applications are only possibilities, but the study has taken a critical step: by understanding the underlying principles behind superconductivity in diamond, researchers can now move beyond simply observing it to actively engineering it.

“We now have a reliable roadmap for engineering diamond superconductors by independently adjusting the material’s core properties,” says Samarth, “By tuning parameters like boron doping density, crystalline orientation, mechanical strain, and dimensionality, we can move beyond simple observation and start designing diamond superconductors for specific roles. There are a lot of exciting possibilities here, for both quantum and classical technology.”

 

Also Read:

Diamond impurities indicate water flows deep in Earth’s mantle too

Recipe for safer batteries — Just add diamonds

Scientists Develop Faster Method To Track Quantum Memory Loss In Qubits

Posted on by
Reply

Researchers in Norway and Denmark have developed a new method to measure how quickly quantum computers lose information, a key obstacle in building stable systems. The study, led by the Norwegian University of Science and Technology and the Niels Bohr Institute, reduces measurement time from about one second to roughly 10 milliseconds. Scientists say the breakthrough allows near real-time tracking of qubit instability, helping identify the causes of information loss.

 

Microsoft Unveils ‘Majorana 1’ Quantum Computing Chip Amid Ongoing Skepticism

Posted on by
Reply

Microsoft has introduced its first quantum computing chip, “Majorana 1,” marking a significant milestone in its pursuit of practical quantum computing. The chip, unveiled on Wednesday, is built on a novel topological core architecture that Microsoft claims will enable quantum computers to solve industrial-scale problems within years rather than decades.

Quantum computers are anticipated to tackle problems beyond the reach of classical computing. Unlike traditional bits, which exist in binary states (0 or 1), quantum bits, or qubits, can exist in multiple states simultaneously, potentially unlocking immense computational power. Competitors such as Google and IBM, alongside smaller firms like IonQ and Rigetti Computing, have also made significant strides in quantum computing, each employing different approaches to achieving quantum supremacy.

At the heart of Majorana 1 is the world’s first “topoconductor,” a new category of material capable of creating a unique state of matter using the Majorana particle—a theoretical entity believed to be its own antiparticle. According to Microsoft, the chip is based on “gate-defined devices” that combine the semiconductor indium arsenide with aluminum, a superconductor.

When the topoconductor is cooled to near absolute zero (approximately -400 degrees Fahrenheit) and exposed to magnetic fields, it is expected to form topological superconducting nanowires with Majorana Zero Modes (MZMs) at their endpoints.

“We took a step back and asked, ‘What kind of transistor does the quantum age require?’ That question led us here,” explained Chetan Nayak, a Microsoft technical fellow. “The combination of quality and details in our new materials stack has enabled a novel type of qubit and, ultimately, an entirely new architecture.”

Microsoft asserts that its topoconductor-based qubits are more stable, compact, and digitally controllable without the trade-offs seen in existing quantum computing alternatives, addressing some critics who raised apprehensions three years ago. The company has also published a research paper in Nature detailing how its researchers successfully engineered and measured the topological qubit’s quantum properties—an essential step toward practical quantum computing.

Ongoing Doubts About Microsoft’s Majorana Claims

Despite Microsoft’s confidence in its topological qubit approach, skepticism persists regarding the fundamental basis of its technology. In 2022, Microsoft published research asserting that it had detected Majorana particles—an essential component of its quantum computing framework. However, physicists from the University of Basel soon challenged these claims, arguing that Microsoft’s findings could be explained by alternative factors.

Their unique properties have sparked renewed interest in recent years, particularly for their potential to serve as stable qubits resistant to decoherence—a major challenge in quantum computing. Decoherence, caused by environmental disturbances, can quickly destroy quantum states, rendering calculations unreliable. If Majorana-based qubits truly exist, they could theoretically circumvent this issue.

However, a 2022 study published in Physical Review Letters by a team led by Prof. Jelena Klinovaja at the University of Basel had cast doubt on Microsoft’s claims. “Microsoft’s approach is promising,” noted Richard David Hess, lead author of the study. “But our calculations suggest that their data could also be explained by other effects unrelated to Majorana particles.”

The challenge in identifying Majorana particles lies in their elusive nature. Researchers rely on nanowires—semiconducting strands thousands of times thinner than a human hair—paired with superconductors to search for telltale quantum signatures. Microsoft’s 2022 findings were based on conductance measurements that indicated anomalies characteristic of Majorana states, alongside observations of a “topological phase”—a concept from topology, a branch of mathematics that examines properties of objects that remain unchanged under continuous transformations.

However, the Basel team conducted mathematical modeling of Microsoft’s experiments and found that similar anomalies and superconducting behaviors could be reproduced by minor imperfections, or “disorder,” within the nanowire itself. “Our results clearly show that disorder plays a significant role in these experiments,” explained Henry Legg, a postdoctoral researcher in Klinovaja’s group.

“While Microsoft’s work represents an exciting step, unambiguously detecting Majorana states and leveraging them for computing remains a formidable challenge,” Klinovaja concluded.