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Category: quantum physics – Page 23

The quantum physics of forgetting information

In a study by TU Wien and FU Berlin, researchers have measured what happens when quantum physical information is lost. This clarifies important connections between thermodynamics, information theory and quantum physics.

Heat and information—these are two very different concepts that, at first glance, appear to have nothing to do with each other. Heat and energy are central concepts in thermodynamics, an important field of physics and even one of its cornerstones. Information theory, on the other hand, is an abstract topic in mathematics.

But as early as the 1960s, physicist Rolf Landauer was able to show that the two are closely related: the deletion of information is inevitably linked to the exchange of energy. You cannot delete a data storage device without releasing heat to the outside world.

Physicists figure out how an electric field can switch off superconductivity

Transistors are fundamental to microchips and modern electronics. Invented by Bardeen and Brattain in 1947, their development is one of the 20th century’s key scientific milestones. Transistors work by controlling electric current using an electric field, which requires semiconductors. Unlike metals, semiconductors have fewer free electrons and an energy band gap that makes it harder to excite electrons.

Doping introduces , enabling current flow under an electric field. This allows for nonlinear current-voltage behavior, making signal amplification or switching possible, as in p–n junctions. Metals, by contrast, have too many that quickly redistribute to cancel external fields, preventing controlled current flow—hence, they can’t be used as traditional transistors.

However, recent advances show promise in ultrathin superconducting metals as potential transistor materials. When cooled below a , these materials carry current with zero resistance. This behavior arises from the formation of Cooper pairs—electrons bound by lattice vibrations—that condense into a coherent quantum state, immune to scattering and energy loss.

“Quantum OS Is Here”: New Operating System Unlocks Full Power of Quantum Computers and Signals the Dawn of a New Era

IN A NUTSHELL 🔬 Researchers have developed QNodeOS, an innovative operating system that unifies different quantum computing technologies. 🌐 QNodeOS features two main units, the CNPU and QNPU, which simplify the management of diverse quantum devices through a single interface. 🔑 The QDriver acts as a translator, converting universal instructions into specific commands for various

Physicists recreate extreme quantum vacuum effects

Using advanced computational modeling, a research team led by the University of Oxford, working in partnership with the Instituto Superior Técnico at the University of Lisbon, has achieved the first-ever real-time, three-dimensional simulations of how intense laser beams alter the “quantum vacuum”—a state once assumed to be empty, but which quantum physics predicts is full of virtual electron-positron pairs.

Excitingly, these simulations recreate a bizarre phenomenon predicted by , known as “vacuum four-wave mixing.” This states that the combined electromagnetic field of three focused can polarize the virtual electron-positron pairs of a vacuum, causing photons to bounce off each other like billiard balls—generating a fourth laser beam in a “light from darkness” process. These events could act as a probe of new physics at extremely high intensities.

“This is not just an academic curiosity—it is a major step toward experimental confirmation of quantum effects that until now have been mostly theoretical,” said study co-author Professor Peter Norreys, Department of Physics, University of Oxford.

Electron Handedness in a Material

A new framework for studying chiral materials puts the emphasis on electron chirality rather than on the asymmetry of the atomic structure.

Chirality is a fundamental feature of nature, manifesting across scales—from elementary particles and molecules to biological organisms and galaxy formation. An object is considered chiral if it cannot be superimposed on its mirror image. In condensed-matter physics, chirality is primarily viewed as a structural asymmetry in the spatial arrangement of atoms within a crystal lattice [1]. A perhaps less familiar fact is that chirality is also a fundamental quantum property of individual electron states [2]. Now, Tatsuya Miki from Saitama University in Japan and colleagues introduce electron chirality as a framework to quantify symmetry breaking in solids, focusing on chiral and related axial materials [3]. The researchers propose a way of measuring electron chirality with photoemission spectroscopy.

Producing superconductors for quantum circuit elements at high temperatures

A project led by the University of Melbourne’s Dr. Manjith Bose and Professor Jeff McCallum, who are also members of the ARC Center of Excellence for Quantum Computation and Communication Technology, has identified a promising class of superconductors that may potentially avoid the need for high levels of cryogenic cooling. These advanced materials can be manufactured, be integrable and be compatible using standard silicon and superconducting electronics approaches.

To optimize the growth of these silicide superconductors, Dr. Bose and Prof. McCallum are making extensive use of high– neutron reflectometry on the Spatz reflectometer at ANSTO’s Australian Center for Neutron Scattering.

Neutrons are an ideal tool for exploring extreme sample environments, such as the high pressure, temperatures or fields that are present when manufacturing circuit elements. This is because neutrons can penetrate through most common metals, allowing one to see reflective thin films deep inside furnaces, magnets and cryo-chambers.

General framework bridges quantum thermodynamics and non-Markovianity

The extraction of work (i.e., usable energy) from quantum processes is a key focus of quantum thermodynamics research, which explores the application of thermodynamics laws to quantum systems. Meanwhile, other quantum physics research has been investigating the non-Markovian dynamics of open quantum systems, which entail the influence of past states on the systems’ future evolution.

Researchers at the University of Nottingham and University of São Paulo have introduced a general and rigorous framework that bridges and non-Markovian dynamics, showing that the latter could serve as a resource that can be exploited to enhance the extraction of work from quantum processes.

Their paper, published in Physical Review Letters, could open new possibilities for the future development of quantum technologies.

Universal law of quantum vortex dynamics discovered in superfluid helium

An international research collaboration featuring scientists from the FAMU-FSU College of Engineering and the National High Magnetic Field Laboratory has discovered a fundamental universal principle that governs how microscopic whirlpools interact, collide and transform within quantum fluids, which also has implications for understanding fluids that behave according to classical physics.

The study, which was published in the Proceedings of the National Academy of Sciences, revealed new insights into vortex dynamics within , a remarkable liquid that exhibits zero-resistance flow at temperatures approaching absolute zero. The research demonstrates that when these quantum vortices intersect and reconnect, they separate faster than their initial approach velocity, creating bursts of energy that characterize turbulence in both quantum and classical fluids.

“Superfluids offer a uniquely clear perspective on turbulence,” said FAMU-FSU College of Engineering Professor Wei Guo, a study co-author. “We’re beginning to understand the universal physics that connects quantum and classical worlds, and that’s an exciting frontier for both science and technology.”

‘String breaking’ observed in 2D quantum simulator

An international team led by Innsbruck quantum physicist Peter Zoller, together with the US company QuEra Computing, has directly observed a gauge field theory similar to models from particle physics in a two-dimensional analog quantum simulator for the first time. The study, published in Nature, opens up new possibilities for research into fundamental physical phenomena.

String breaking occurs when the string between two strongly bound particles, such as a quark-antiquark pair, breaks and new particles are created. This concept is central to understanding the that occur in (QCD), the theory that describes the binding of quarks in protons and neutrons.

String breaking is extremely difficult to observe experimentally, as it only occurs in nature under extreme conditions. The recent work by scientists from the Universities of Innsbruck and Harvard, the ÖAW-Institute for Quantum Optics and Quantum Information (IQOQI) and the quantum computer company QuEra shows for the first time how this phenomenon can be reproduced in an analog quantum .