Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: computing

New evidence for a particle system that ‘remembers’ its previous quantum states

In the future, quantum computers are anticipated to solve problems once thought unsolvable, from predicting the course of chemical reactions to producing highly reliable weather forecasts. For now, however, they remain extremely sensitive to environmental disturbances and prone to information loss.

A new study from the lab of Dr. Yuval Ronen at the Weizmann Institute of Science, published in Nature, presents fresh evidence for the existence of non-Abelian anyons—exotic particles considered prime candidates for building a fault-tolerant quantum computer. This evidence was produced within bilayer graphene, an ultrathin carbon crystal with unusual electronic behavior.

In quantum mechanics, particles also behave like waves, and their properties are described by a wave function, which can represent the state of a single particle or a system of particles. Physicists classify particles according to how the wave function of two identical particles changes when they exchange places. Until the 1980s, only two types of particles were known: bosons (such as photons), whose wave function remains unchanged when they exchange places, and fermions (such as electrons), whose wave function becomes inverted.

Antiferromagnetic metal exhibits diode-like behavior without external magnetic field

Antiferromagnetic (AF) materials are made up of atoms or molecules with atomic spins that align in antiparallel directions of their neighbors. The magnetism of each individual atom or molecule is canceled out by the one next to it to produce zero net magnetization.

Researchers in Japan have now discovered that an AF material, NdRu2Al10, has the ability to produce a diode-like effect, meaning electrical current can flow in one direction but not the other (nonreciprocal), similar to the junction of two semiconductors. Their research is published in Physical Review Letters.

Going further with fusion, together

At 4 a.m., while most of New Jersey slept, a Princeton Plasma Physics Laboratory (PPPL) physicist sat at his computer connected to a control room 3,500 miles away in Oxford, England. Years of experience running fusion experiments in the U.S. helped guide the U.K. team through delicate adjustments as they worked together to coax particles of plasma—the fourth state of matter—to temperatures that match those found at the heart of the sun.

This late-night, intercontinental collaboration happened many times from 2019 to 2024 during critical experiments at Tokamak Energy’s ST40 facility. It’s just one example of how PPPL is meeting the moment, leading collaborative efforts with private companies and other public institutions to make fusion power practical.

Fusion, the process of combining atoms to release energy, could be the source of a nearly inexhaustible supply of electricity. But there are still challenging scientific and engineering issues to overcome in the quest for power. That’s why scientists are increasingly working together to take fusion further.

3D-Printed “Light Cages” Could Solve One of Quantum Networking’s Biggest Problems

A new chip-based quantum memory uses 3D-printed “light cages” to store light in atomic vapor with high precision. Quantum information storage plays a central role in the development of the quantum internet and future quantum computers. Today’s quantum communication systems are limited by signal l

Algorithm matches drugs to glioblastoma’s diverse cell types, offering hope for individualized therapies

Researchers have developed a new computational approach that uncovers possible drugs for specific cellular targets for treating glioblastoma, a lethal brain tumor. This approach enabled them to predict more effective treatment combinations to fight the disease on an individualized basis.

This laboratory and computational research effort was led by scientists at Georgetown’s Lombardi Comprehensive Cancer Center.

“The cellular targets we identified could be key to effectively fighting a disease that has seen only one new targeted drug approved in the last two decades,” says Nagi G. Ayad, Ph.D., senior author, associate director for translational research, and professor of oncology at Georgetown Lombardi.

Electrons that lag behind nuclei in 2D materials could pave way for novel electronics

One of the great successes of 20th-century physics was the quantum mechanical description of solids. This allowed scientists to understand for the first time how and why certain materials conduct electric current and how these properties could be purposefully modified. For instance, semiconductors such as silicon could be used to produce transistors, which revolutionized electronics and made modern computers possible.

To be able to mathematically capture the complex interplay between electrons and atomic nuclei and their motions in a solid, physicists had to make some simplifications. They assumed, for example, that the light electrons in an atom follow the motion of the much heavier atomic nuclei in a crystal lattice without any delay. For several decades, this Born-Oppenheimer approximation worked well.

Error-correction technology to turn quantum computing into real-world power

Ripples spreading across a calm lake after raindrops fall—and the way ripples from different drops overlap and travel outward—is one image that helps us picture how a quantum computer handles information.

Unlike conventional computers, which process digital data as “0 or 1,” quantum computers can process information in an in-between state where it is “both 0 and 1.” These quantum states behave like waves: they can overlap, reinforcing one another or canceling one another out. In computations that exploit this property, states that lead to the correct answer are amplified, while states that lead to wrong answers are suppressed.

Thanks to this interference between waves, a quantum computer can sift through many candidate answers at once. Our everyday computers take time because they evaluate each candidate one by one. Quantum computers, by contrast, can narrow down the answer in a single sweep—earning them the reputation of “dream machines” that could solve in an instant problem that might take hundreds of years on today’s computers.

A wireless subdural-contained brain–computer interface with 65,536 electrodes and 1,024 channels

A flexible micro-electrocorticography brain–computer interface that integrates a 256 × 256 array of electrodes, signal processing, data telemetry and wireless powering on a single complementary metal–oxide–semiconductor substrate can provide stable, chronic in vivo recordings.

Diode-Like Behavior Arising from Antiferromagnetism

An antiferromagnet with a zigzag magnetic structure exhibits a diode effect that has potential applications in spintronics.

In a traditional diode, current flows in one direction only, thanks to an internal charge imbalance. Researchers have now shown a diode-like effect in an antiferromagnet with a zigzag magnetic structure [1]. The underlying mechanism is different from that in traditional diodes, as the zigzag pattern creates a combined magnetic and electric field that favors current flow in one direction. The strength of the diode effect in the antiferromagnet is relatively small, but rather than exploiting the effect to make a diode for conventional circuits, the team foresees possible applications in spintronics, devices that make use of electron spins.

A typical diode is a junction between two semiconductors having different charge carriers. The charge imbalance across this junction restricts current to flow in only one direction. Diode-like behavior can, in principle, occur in a single material, but it requires that the material’s internal structure is asymmetric in a particular way. This asymmetry should produce two effects: an internal electric field and an internal magnetic field. When those two fields are perpendicular to each other, they can exert a one-way force—called a toroidal moment—on electrons moving through the material, explains Kenta Sudo from Tohoku University in Japan.

/* */