Quantum Physics

Can a single particle have a temperature? It may seem impossible with our standard understanding of temperature, but columnist Jacklin Kwan finds that it’s not exactly ruled out in the quantum realm

John Martinis has already revolutionised quantum computing twice. Now, he is working on another radical rethink of the technology that could deliver machines with unrivalled capabilities

Quantum technologies, devices and systems that process, store, detect, or transfer information leveraging quantum mechanical effects, have the potential to outperform classical technologies in a variety of tasks. An ongoing quest within quantum engineering is the realization of a so-called quantum internet: a network conceptually analogous to today's internet, in which distant nodes are linked through shared quantum resources, most notably quantum entanglement.

A team of theoretical researchers has found duality can unveil non-invertible symmetry protected topological phases, which can lead to researchers understanding more about the properties of these phases, and uncover new quantum phases. Their study is published in Physical Review Letters.

Researchers have demonstrated that a nanoparticle of 7,000 sodium atoms can act as a wave, creating a record-setting superposition.

Recently, scientists from institutions including the University of Science and Technology of China made a fundamental breakthrough in nuclear-spin quantum precision measurement. They developed the first intercity nuclear-spin-based quantum sensor network, which experimentally constrains the axion topological-defect dark matter and surpasses the astrophysical limits. The study is published in the journal Nature.

Quantum chaos describes chaotic classical dynamical systems in terms of quantum theory, but simulations of these systems are limited by computational resources. However, one team seems to have found a way by leveraging error mitigation and specialized circuits on a 91-qubit superconducting quantum processor. Their results are published in Nature Physics.

A new light-based breakthrough could help quantum computers finally scale up. Stanford researchers created miniature optical cavities that efficiently collect light from individual atoms, allowing many qubits to be read at once. The team has already demonstrated working arrays with dozens and even hundreds of cavities. The approach could eventually support massive quantum networks with millions of qubits.

In some solid materials under specific conditions, mutual Coulomb interactions shape electrons into many-body correlated states, such as Wigner crystals, which are essentially solids made of electrons. So far, the Wigner crystal state remains sensitive to various experimental perturbations. Uncovering their internal structure and arrangement at the atomic scale has proven more challenging.

Where is physics headed? No one knows for sure, but Beyond the Quantum by Antony Valentini is a striking new book that reminds us what a big idea really looks like, finds Jon Cartwright

Researchers from Regensburg and Birmingham have overcome a fundamental limitation of optical microscopy. With the help of quantum mechanical effects, they succeeded for the first time in performing optical measurements with atomic resolution. Their work is published in the journal Nano Letters.

Time-dependent driving has become a powerful tool for creating novel nonequilibrium phases such as discrete time crystals and Floquet topological phases, which do not exist in static systems. Breaking continuous time-translation symmetry typically leads to the outcome that driven quantum systems absorb energy and eventually heat up toward a featureless infinite-temperature state, where coherent structure is lost.

Scientists achieve optical measurements at atomic scales using quantum electron tunneling, surpassing conventional microscopy limits by nearly 100,000 times with standard lasers.

Nu Quantum will open a Spanish subsidiary following its $60 million series A funding round, announced last month, in which the Spanish government contributed €9.75 million to the company's raised total. The launch of Nu Quantum's subsidiary will be in partnership with the Spanish Society for Technological Transformation (SETT). Nu Quantum CEO Carmen Palacios-Berraquero (right) and Oscar López Agueda (middle), Spain’s Minister for Digital Transformation and Public Administration, announced the public-private partnership live in Madrid at the Science for Industry (S4i) forum. Courtesy of Nu Quantum. Nu Quantum’s subsidiary will focus on industrialization of the quantum networking unit (QNU) and the development...

Silicon carbide is for photonic circuits and quantum devices. Atomic layer processing boosts SiC waveguides and resonators, improving performance.

For quantum computers to function, they must be kept at extremely low temperatures. However, today's cooling systems also generate noise that interferes with the fragile quantum information they are meant to protect. Now, researchers at Chalmers University of Technology in Sweden have developed an entirely new type of quantum refrigerator, which is partly driven by the noise itself. This refrigerator enables very precise control over heat and energy flows and could play an important role in scaling up quantum technology.

There is no measurement that can directly observe the wave function of a quantum mechanical system, but the wave function is still enormously useful as its (complex) square represents the probability density of the system or elements of the system. But for a confined system, the wave function can be inferred.

Quantum computers need extreme cold to work, but the very systems that keep them cold also create noise that can destroy fragile quantum information. Scientists in Sweden have now flipped that problem on its head by building a tiny quantum refrigerator that actually uses noise to drive cooling instead of fighting it. By carefully steering heat at unimaginably small scales, the device can act as a refrigerator, heat engine, or energy amplifier inside quantum circuits.

The Einstein–de Haas effect, which links the spin of electrons to macroscopic rotation, has now been demonstrated in a quantum fluid by researchers at Science Tokyo. The team observed this effect in a Bose–Einstein condensate of europium atoms, showing that a change in magnetization causes the coherent transfer of angular momentum from atomic spins to fluid motion, thereby experimentally demonstrating that angular momentum is conserved at the quantum level.

Researchers developed a simple quantum refrigerator that uses environmental noise to control heat and energy flows, aiding precise cooling for quantum computing.

Even given a set of possible quantum states for our cosmos, it's impossible for us to determine which one of them is correct

The Einstein-de Haas effect has been observed in a quantum fluid, showing that changes in magnetization transfer angular momentum from atomic spins to collective motion.

Author(s): Xiang Zhan and Peng XueEntanglement and so-called magic states have long been viewed as the key resources for quantum error correction. Now contextuality, a hallmark of quantum theory, joins them as a complementary resource. [Physics 19, 9] Published Wed Jan 28, 2026

A century ago, Erwin Schrödinger came up with an equation that says how the quantum world behaves. Now scientists are asking what happens when the observer is part of that world

Researchers from the Institute of Metal Research (IMR) of the Chinese Academy of Sciences have stretched a chain of gold atoms by a record-breaking 46%, providing direct evidence of how fundamental metal bonds behave under extreme deformation. This study also reveals how structural changes at the atomic scale influence electrical transport.

Scientists have unveiled a new approach to powering quantum computers using quantum batteries—a breakthrough that could make future computers faster, more reliable, and more energy efficient.

A light has emerged at the end of the tunnel in the long pursuit of developing quantum computers, which are expected to radically reduce the time needed to perform some complex calculations from thousands of years down to a matter of hours.

Deformed nucleus makes multi-ion design easier The post Ion-clock transition could benefit quantum computing and nuclear physics appeared first on Physics World.

A century-old thought experiment on wave–particle duality is brought into the laboratory using a single trapped atom The post Einstein’s recoiling slit experiment realized at the quantum limit appeared first on Physics World.

Researchers uncovered a powerful new way to engineer exotic quantum states, revealing a robust and tunable three‑dimensional flat electronic band in an ultrathin kagome metal, an achievement long thought to be nearly impossible.

Quantum technology has the potential to transform society. But how can you effectively inform the public about such complex and enigmatic science and technology? Ph.D. candidate Aletta Meinsma explored this.

Quantum computing represents a potential breakthrough technology that could far surpass the technical limitations of modern-day computing systems for some tasks. However, putting together practical, large-scale quantum computers remains challenging, particularly because of the complex and delicate techniques involved.

A promising technology for producing next-generation, vivid-color displays with metal-halide perovskite emitters demonstrates record quantum yield and achieves luminescence stability compatible with commercial use. Colloidal perovskite nanocrystals (PeNCs) offer strong light absorption capabilities and high photoluminescence quantum yield (PLQY), but they are vulnerable to degradation induced by light, heat, air, and moisture. Researchers at Seoul National University identified the pathway for PeNC degradation and developed a stabilization strategy to overcome the material’s degradation limits. They resolved the long-standing instability of perovskite emitters and fabricated perovskite solid-state emitters that...

Quantum technology has reached a turning point, echoing the early days of modern computing. Researchers say functional quantum systems now exist, but scaling them into truly powerful machines will require major advances in engineering and manufacturing. By comparing different quantum platforms, the study reveals both impressive progress and steep challenges ahead. History suggests the payoff could be enormous—but not immediate.

Researchers have developed a unique approach to delivering laser light through photonic circuitry for controlling the states of trapped ions, representing a potential novel method for overcoming challenges in quantum computing technology.

Physicists found why holes move slower than electrons in silicon: not defects, but higher intrinsic mass, supporting CMOS-based quantum, cryogenic, and space devices.

Some things are easier to achieve if you're not alone. As researchers from the University of Rostock, Germany have shown, this very human insight also applies to the most fundamental building blocks of nature.

An old puzzle in particle physics has been solved: How can quantum field theories be best formulated on a lattice to optimally simulate them on a computer? The answer comes from AI.

IonQ has entered into a definitive agreement to acquire SkyWater Technology, the largest exclusively U.S.-based, pure-play semiconductor foundry. The proposed cash and stock transaction carries a value of approximately $1.8 billion. The transaction is expected to close in the second or third quarter of 2026. The combination of IonQ and SkyWater will create the first of its kind vertically integrated quantum platform company, IonQ said. As a result, the combined company is expected to pull forward functional testing of its 200,000 qubit quantum processing units (QPUs) in 2028 enabling over 8000 ultra-high fidelity logical qubits. “With secure, U.S.-based design, packaging and chip fabrication — IonQ will benefit...

Australian spin-out Silicon Quantum Computing makes the case with a modality-leading 11-qubit processor The post Could silicon become the bedrock of quantum computers? appeared first on Physics World.

Matter-wave diffraction in short-lived electron-positron atom.

Researchers have demonstrated that quantum entanglement can link atoms across space to improve measurement accuracy. By splitting an entangled group of atoms into separate clouds, they were able to measure electromagnetic fields more precisely than before. The technique takes advantage of quantum connections acting at a distance. It could enhance tools such as atomic clocks and gravity sensors.

‘P4Q’ to make photonic chips for quantum apps more reliable and scalable.

For the first time, physicists have generated and observed stable bright matter-wave solitons with attractive interactions within a grid of laser light.

A record-breaking experiment shows that a cluster of thousands of atoms can act like a wave as well as a particle

Cryogenic 4D-STEM reveals how charge density waves form, fragment, and persist across a phase transition.

“Elegant” result has implications for a quantum internet The post Encrypted qubits can be cloned and stored in multiple locations appeared first on Physics World.

Quantum computers, systems that process information leveraging quantum mechanical effects, are expected to outperform classical computers on some complex tasks. Over the past few decades, many physicists and quantum engineers have tried to demonstrate the advantages of quantum systems over their classical counterparts on specific types of computations.

Primordial black holes could rewrite our understanding of dark matter and the early universe. A record-breaking detection at the bottom of the Mediterranean Sea has some physicists wondering if we just spotted one. The post Monster Neutrino Could Be a Messenger of Ancient Black Holes first appeared on Quanta Magazine

Researchers have demonstrated how quantum mechanical entanglement can be used to measure several physical parameters simultaneously with greater precision.

Researchers at the University of Basel and the Laboratoire Kastler Brossel have demonstrated how quantum mechanical entanglement can be used to measure several physical parameters simultaneously with greater precision.

Scientists have created 3D printed surfaces featuring intricate textures that can be used to bounce unwanted gas particles away from quantum sensors, allowing useful particles like atoms to be delivered more efficiently, which could help improve measurement accuracy.

Scientists have created 3D printed surfaces featuring intricate textures that can be used to bounce unwanted gas particles away from quantum sensors, allowing useful particles like atoms to be delivered more efficiently, which could help improve measurement accuracy.

Quantum computers, systems that process information leveraging quantum mechanical effects, could reliably tackle various computational problems that cannot be solved by classical computers. These systems process information in the form of qubits, units of information that can exist in two states at once (0 and 1).

Photonics West presentations compare three complementary hybrid laser architectures.

Quantum state diffusion framework makes it possible to characterize quantum measurement in terms of entropy production The post Modelling wavefunction collapse as a continuous flow yields insights on the nature of measurement appeared first on Physics World.

Quantum computers could rapidly solve complex problems that would take the most powerful classical supercomputers decades to unravel.

When quantum spins interact, they can produce collective behaviors that defy long-standing expectations. Researchers have now shown that the Kondo effect behaves very differently depending on spin size. In systems with small spins, it suppresses magnetism, but when spins are larger, it actually promotes magnetic order. This discovery uncovers a new quantum boundary with major implications for future materials.

Scientists are learning how to temporarily reshape materials by nudging their internal quantum rhythms instead of blasting them with extreme lasers. By harnessing excitons, short-lived energy pairs that naturally form inside semiconductors, researchers can alter how electrons behave using far less energy than before. This approach achieves powerful quantum effects without damaging the material, overcoming a major barrier that has limited progress for years.

Research in the lab of UC Santa Barbara materials professor Stephen Wilson is focused on understanding the fundamental physics behind unusual states of matter and developing materials that can host the kinds of properties needed for quantum functionalities.

Light and matter can remain at separate temperatures even while interacting with each other for long periods, according to new research that could help scale up an emerging quantum computing approach in which photons and atoms play a central role.

Atomic-scale defects in 2D materials show terahertz spin splitting, pointing to robust spin qubits and single-photon emitters at higher temperatures.

Can a small lump of metal be in a quantum state that extends over distant locations? A research team at the University of Vienna answers this question with a resounding yes. In the journal Nature, physicists from the University of Vienna and the University of Duisburg-Essen show that even massive nanoparticles consisting of thousands of sodium atoms follow the rules of quantum mechanics. The experiment is currently one of the best tests of quantum mechanics on a macroscopic scale.

A team of researchers led by the University of Warwick has developed the first unified framework for detecting "spacetime fluctuations"—tiny, random distortions in the fabric of spacetime that appear in many attempts to unite quantum physics and gravity.

Experiments reveal that metallic nanoparticles thousands of atoms wide can exist in quantum superposition, providing a stringent test of quantum mechanics.

Scientists from the National University of Singapore (NUS) have discovered that atomic-scale substitutional dopants in ultra-thin two-dimensional (2D) materials can act as stable quantum systems operating at terahertz (THz) frequencies.

A new study shows how frustrated magnetic interactions in a triangular lattice create unconventional, fluctuating states for quantum technologies.

A research team led by the University of Oxford's Department of Engineering Science has shown it is possible to engineer a quantum mechanical process inside proteins, opening the door to a new class of quantum-enabled biological technologies.

Quantum technologies, systems that process, transfer or store information leveraging quantum mechanical effects, could tackle some real-world problems faster and more effectively than their classical counterparts. In recent years, some engineers have been focusing their efforts on the development of quantum communication systems, which could eventually enable the creation of a "quantum internet" (i.e., an equivalent of the internet in which information is shared via quantum physical effects).

In order to make quantum computers large and stable enough to fulfill their promises, researchers are developing trapped-ion quantum computers based on ultra-compact photonic chips. While these devices offer greater scalability than existing systems that rely on bulky optical equipment, the issue of cooling has been a significant stumbling block. To address this, researchers at MIT and MIT Lincoln Laboratory have found a way to cool trapped ions using photonic chips, achieving cooling to about 10× below the limit of standard laser cooling. Key to the technique is a photonic chip that incorporates precisely designed antennas to manipulate beams of tightly focused, intersecting light. The researchers’ initial...

Even very slight environmental noise, such as microscopic vibrations or magnetic field fluctuations a hundred times smaller than Earth's magnetic field, can be catastrophic for quantum computing experiments with trapped ions.

One of the discoveries that fundamentally distinguished the emerging field of quantum physics from classical physics was the

A hundred years ago, quantum mechanics was a radical theory that baffled even the brightest minds. Today, it's the backbone of technologies that shape our lives, from lasers and microchips to quantum computers and secure communications.

The strange principle of quantum entanglement baffled Albert Einstein. Yet finally putting quantum weirdness to the ultimate test, and embracing the results, turned out to be a revolutionary idea

Quantum mechanics is rich with paradoxes and contradictions. It describes a microscopic world in which particles exist in a superposition of states—being in multiple places and configurations all at once, defined mathematically by what physicists call a "wavefunction." But this runs counter to our everyday experience of objects that are either here or there, never both at the same time.

A team from UNIGE shows that it is possible to determine the state of a quantum system from indirect measurements when it is coupled to its environment.

A new unified theory connects two fundamental domains of modern quantum physics: It joins two opposite views of how a single exotic particle behaves in a many-body system, namely as a mobile or static impurity among a large number of fermions, a so-called Fermi sea.

Quantum computers could revolutionize everything from drug discovery to business analytics—but their incredible power also makes them surprisingly vulnerable. New research from Penn State warns that today’s quantum machines are not just futuristic tools, but potential gold mines for hackers. The study reveals that weaknesses can exist not only in software, but deep within the physical hardware itself, where valuable algorithms and sensitive data may be exposed.

The mystery of quantum phenomena inside materials—such as superconductivity, where electric current flows without energy loss—lies in when electrons move together and when they break apart. KAIST researchers have succeeded in directly observing the moments when electrons form and dissolve ordered patterns.

Quantum technologies are cutting-edge systems that can process, transfer, or store information leveraging quantum mechanical effects, particularly a phenomenon known as quantum entanglement. Entanglement entails a correlation between two or more distant particles, whereby measuring the state of one also defines the state of the others.

Lightwave Logic, a developer of electro-optic (EO) polymer technology, and QPICs, a newly established foundry dedicated to advancing photonic integrated circuit (PIC) based quantum technology as part of the Quantum Tech Hub initiative in Colorado, have signed a memorandum of understanding to accelerate the use of electro-optic polymers for the commercialization of photonic quantum circuits. Per the agreement, QPICs will develop process design kits (PDKs) with Lightwave Logic’s proprietary polymer platform and encapsulation processes with the goal of accelerating PIC production timelines for quantum computing customers. The availability of the PDK will allow these customers to design custom solutions based on silicon circuits...

Quantum effects in Kondo lattices can determine whether a system behaves magnetically or non-magnetically, opening new avenues for designing future quantum materials and technologies.