Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: quantum physics

Physicists repair flaw of established quantum resource theorem

Quantum information theory is a field of study that examines how quantum technologies store and process information. Over the past decades, researchers have introduced several new quantum information frameworks and theories that are informing the development of quantum computers and other devices that operate leveraging quantum mechanical effects.

These include so-called resource theories, which outline the transformations that can take place in quantum systems when only a limited number of operations are allowed.

In 2008, two scientists at Imperial College London introduced what they termed the generalized quantum Stein’s lemma, a mathematical theorem that describes how well quantum states can be distinguished from one another. In this generalized setting, one typically considers multiple identical copies of a specific state (the null hypothesis) and tests them against a composite alternative hypothesis, i.e., a set of states (e.g., resource-free states).

Real-life experiment shows Niels Bohr was right in a theoretical debate with Einstein

Scientists in China have performed an experiment first proposed by Albert Einstein almost a century ago when he sought to disprove the quantum mechanical principle of complementarity put forth by Niels Bohr and his school of physicists. Bohr claimed there are properties of particles that cannot simultaneously be measured. The new result backs up the Copenhagen school yet again, with the potential to shed light on other, less settled questions in quantum mechanics.

When they met at physics conferences, Albert Einstein and Niels Bohr liked to kick back and debate about quantum mechanics. Einstein, always skeptical of the standard picture of quantum mechanics then being developed, liked to claim he had found holes and inconsistencies in Bohr’s interpretation, and Bohr was always up for the challenge.

At the 1927 Solvay conference in Brussels, the two Nobel Laureates had perhaps their most famous parley, with Einstein famously proclaiming, “God does not play dice with the universe.” In particular, Einstein proposed an experiment he thought would reveal the essential contradiction in the principle of complementarity, which held that pairs of properties of particles, such as position and momentum, and frequency and lifetime, cannot be measured at the same time. Complementarity undergirds the concepts of wave-particle duality and Heisenberg’s uncertainty principle.

Hunting for dark matter axions with a quantum-powered haloscope

Axions are hypothetical light particles that could solve two different physics problems, as they could explain why some nuclear interactions don’t violate time symmetry and are also promising dark matter candidates. Dark matter is a type of matter that does not emit, reflect or absorb light, and has never been directly observed before.

Axions are very light particles theorized to have been produced in the early universe but that would still be present today. These particles are expected to interact very weakly with ordinary matter and sometimes convert into photons (i.e., light particles), particularly in the presence of a strong magnetic field.

The QUAX (Quest for Axions/QUaerere AXion) collaboration is a large group of researchers based at different institutes in Italy, which was established to search for axions using two haloscopes located in Italy at Laboratori Nazionali di Legnaro (LNL) and Laboratori Nazionali di Frascati (LNF), respectively.

This Quantum Gas Refuses To Follow the Rules of Classical Physics

Researchers at TU Wien have developed a one-dimensional “quantum wire” using a gas of ultracold atoms. In this system, both mass and energy can move freely without friction or energy loss. In everyday physics, transport refers to the movement of something from one place to another. This can inclu

Josephson junction behavior observed with only one superconductor and iron barrier

Separate two superconductors with a thin layer of material and something strange happens.

Their superconductivity—a property driven by paired electrons that allows electricity to flow without energy loss—can leak into the barrier and link together, synchronizing their behavior despite the separation.

This device is known as a Josephson junction. It’s the foundational building block of quantum computers and advances of it won the 2025 Nobel Prize in Physics.

Dual-cation strategy boosts upconversion efficiency in stable oxide perovskites

Researchers at the Hefei Institutes of Physical Science of the Chinese Academy of Sciences have developed a new way to significantly enhance upconversion luminescence in oxide perovskites, a class of materials known for their thermal and chemical stability but limited optical efficiency.

Led by Professor Jiang Changlong, the team introduced a dual-cation substitution strategy in titanate perovskites by precisely adjusting the sodium-to-lithium ratio at the crystal’s A-site. This controlled substitution triggers a structural transition that improves energy transfer between rare-earth ions, resulting in a marked increase in luminescence intensity and quantum yield.

The findings are published in Journal of Alloys and Compounds.

Researchers discover a new superfluid phase in non-Hermitian quantum systems

A stable “exceptional fermionic superfluid,” a new quantum phase that intrinsically hosts singularities known as exceptional points, has been discovered by researchers at the Institute of Science Tokyo.

Their analysis of a non-Hermitian quantum model with spin depairing shows that dissipation can actively stabilize a superfluid with these singularities embedded within it. The work reveals how lattice geometry dictates the phase’s stability and provides a path to realizing it in experiments with ultracold atoms.

In the quantum world, open quantum systems are those where particle loss and directional asymmetry are fundamental features. These systems can no longer be described by conventional mathematics.

Evidence of a quantum spin liquid ground state in a kagome material

Quantum spin liquids are exotic states of matter in which spins (i.e., the intrinsic angular momentum of electrons) do not settle into an ordered pattern and continue to fluctuate, even at extremely low temperatures. This state is characterized by high entanglement, a quantum effect that causes particles to become linked so that the state of one affects the others’ states, even over long distances.

Researchers at SLAC National Accelerator Laboratory and Stanford University recently gathered evidence of intrinsic quantum spin liquid behavior in a kagome material, a magnetic material in which atoms are arranged in a particular pattern known as a kagome lattice. Their findings, published in Nature Physics, could help to further delineate the fundamental principles underpinning quantum spin liquid states.

“I’ve been interested in understanding quantum spin liquids for the past 20+ years,” Young S. Lee, senior author of the paper, told Phys.org. “These are fascinating new states of quantum matter. In principle, their ground states may possess long-range quantum entanglement, which is extremely rare in real materials.

/* */