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Laser-cooled atomic gases, gases of atoms chilled to temperatures around absolute zero using laser technologies, have proved to be versatile physical platforms to study and control quantum phenomena. When these atomic gases interact with light inside an optical cavity (i.e., a structure designed to trap and enhance light), they can give rise to effects that can be leveraged to realize quantum sensing or simulate complex quantum systems.

Using loaded in optical cavities, physicists have observed various intriguing effects, including self-organization phase transitions, characterized by the spontaneous arrangement of the gas atoms into ordered patterns, lasing and the preservation of quantum coherence. Generally, however, these effects are only observed for short times, as new atoms need to be reloaded in the cavity for them to be produced again.

Researchers at JILA, a joint research institute of the University of Colorado-Boulder and the National Institute of Standards and Technology, recently demonstrated continuous lasing that lasted hours using laser-cooled strontium-88 (88 Sr) atoms loaded into a ring (i.e., circular) . Their paper, published in Nature Physics, could open new possibilities for the development of ultra-quiet lasers, as well as quantum computers and sensing technologies.

Solar cells based on perovskites, materials with a characteristic crystal structure first unveiled in the mineral calcium titanate (CaTiO3), have emerged as a promising alternative to conventional silicon-based photovoltaics. A key advantage of these materials is that they could yield high power conversion efficiencies (PCEs), yet their production costs could be lower.

Perovskite films can exist in different structural forms, also referred to as phases. One is the so-called α-phase (i.e., a photoactive black phase), which is the most desirable phase for the efficient absorption of light and the transport of charge carriers. The δ-phase, on the other hand, is an intermediate phase characterized by a different atom arrangement and reduced photoactivity.

Researchers at the University of Toledo, Northwestern University, Cornell University and other institutes recently introduced a new strategy to control the crystallization process in -based , stabilizing the δ-phase while facilitating their transition to the α-phase. Their proposed approach, outlined in a paper in Nature Energy, enables the formation of Lewis bases on perovskites on demand to optimize crystallization, which can enhance the efficiency and stability of solar cells.

Altermagnets, which exhibit momentum-dependent spin splitting without spin–orbit coupling (SOC) or net magnetization, have recently attracted significant international attention.

A team led by Prof. Liu Junwei from the Department of Physics at the Hong Kong University of Science and Technology (HKUST), along with their experimental collaborators, published their latest research findings in Nature Physics, which unveiled the first experimental observation of a two-dimensional layered altermagnet, validating the in Nature Communications made by Prof. Liu in 2021.

The realization and control of spin-polarized electronic states in solids are crucial for spintronics for encoding and processing information. Spin polarization is typically generated by coupling an electron’s spin to other degrees of freedom, such as orbital or .

Researchers at Rensselaer Polytechnic Institute (RPI) are tackling one of the most complex challenges in the world of quantum information—how to create reliable, scalable networks that can connect quantum systems over distances.

Their work has resulted in two publications in Physical Review Letters and Science Advances, bringing us one step closer to realizing large-scale networked , or even the quantum internet.

The research team, which includes faculty members from the RPI Department of Physics, Applied Physics, and Astronomy, and the Department of Computer Science, is led by Assistant Professor Xiangyi Meng, Ph.D. Their research focuses on designing that use entanglement—a phenomenon where quantum particles become mysteriously correlated.

A theoretical study by RIKEN physicists, published in Physics Letters B, has accurately determined the interaction between a charmonium and a proton or neutron for the first time.

From two galaxies colliding to an electron jettisoned from a nucleus, all interactions in the universe can be described in terms of just four fundamental forces.

Gravity and the are the two we are familiar with in everyday life, while the weak and strong forces operate over minuscule distances—roughly the size of an atomic nucleus or smaller.

The quantum black hole with (almost) no equations by Professor Gerard ‘t Hooft.

How to reconcile Einstein’s theory of General Relativity with Quantum Mechanics is a notorious problem. Special relativity, on the other hand, was united completely with quantum mechanics when the Standard Model, including Higgs mechanism, was formulated as a relativistic quantum field theory.

Since Stephen Hawking shed new light on quantum mechanical effects in black holes, it was hoped that black holes may be used to obtain a more complete picture of Nature’s laws in that domain, but he arrived at claims that are difficult to use in this respect. Was he right? What happens with information sent into a black hole?

The discussion is not over; in this lecture it is shown that a mild conical singularity at the black hole horizon may be inevitable, while it doubles the temperature of quantum radiation emitted by a black hole, we illustrate the situation with only few equations.

About the Higgs Lecture.

The Faculty of Natural, Mathematical & Engineering Sciences is delighted to present the Annual Higgs Lecture. The inaugural Annual Higgs Lecture was delivered in December 2012 by its name bearer, Professor Peter Higgs, who returned to King’s after graduating in 1950 with a first-class honours degree in Physics, and who famously predicted the Higgs Boson particle.

Sir Joseph John Thomson (18 December 1856 – 30 August 1940) was an English physicist who received the Nobel Prize in Physics in 1906 “in recognition of the great merits of his theoretical and experimental investigations on the conduction of electricity by gases.” [ 1 ]

In 1897, Thomson showed that cathode rays were composed of previously unknown negatively charged particles (now called electrons), which he calculated must have bodies much smaller than atoms and a very large charge-to-mass ratio. [ 2 ] Thomson is also credited with finding the first evidence for isotopes of a stable (non-radioactive) element in 1913, as part of his exploration into the composition of canal rays (positive ions). His experiments to determine the nature of positively charged particles, with Francis William Aston, were the first use of mass spectrometry and led to the development of the mass spectrograph. [ 2 ] [ 3 ]

Thomson was awarded the 1906 Nobel Prize in Physics for his work on the conduction of electricity in gases. [ 4 ] Thomson was also a teacher, and seven of his students went on to win Nobel Prizes: Ernest Rutherford (Chemistry 1908), Lawrence Bragg (Physics 1915), Charles Barkla (Physics 1917), Francis Aston (Chemistry 1922), Charles Thomson Rees Wilson (Physics 1927), Owen Richardson (Physics 1928) and Edward Victor Appleton (Physics 1947). [ 5 ] Only Arnold Sommerfeld’s record of mentorship offers a comparable list of high-achieving students.

Researchers at Swansea University have discovered a way to use mirrors to dramatically reduce the quantum noise that disturbs tiny particles—a breakthrough that might seem magical but is rooted in quantum physics.

When scientists measure extremely small objects, such as nanoparticles, they face a difficult challenge: simply observing these particles disturbs them. This happens because photons, particles of light, used for measurement “kick” the they hit, an effect known as “backaction.”

In a new study published in Physical Review Research, a team from the university’s Physics Department has revealed a remarkable connection, that this relationship works both ways.

Swinburne researchers have discovered unexpected and entirely new quantum behaviors that only occur in one-dimensional systems, such as electrical current. Their new paper, published in Physical Review Letters, explores a fundamental question in quantum physics: what happens when a single “impurity” particle, such as an atom or electron, is introduced into a tightly packed crowd of identical particles.

Nearly every material in the world contains small imperfections or extra particles; understanding how these “outsiders” interact with their environment is key to figuring out how materials conduct electricity, create light, or respond to external forces.

A team at the Center for Quantum Technology Theory at Swinburne studied this in the setting of a one-dimensional optical lattice (a kind of artificial crystal made with ) using a well-known theoretical framework called the Fermi-Hubbard model.

For the first time, a research team has successfully produced one of the most neutron-rich isotopes, hydrogen-6, in an electron scattering experiment.

The experiment at the spectrometer facility at the Mainz Microtron (MAMI) was a joint effort among the A1 Collaboration at the Institute of Nuclear Physics at Johannes Gutenberg University Mainz (JGU) and scientists from China and Japan. The team presents a new method for investigating light, neutron-rich nuclei and challenges our current understanding of multi-nucleon interactions.

“This measurement could only be carried out thanks to the unique combination of the excellent quality of the MAMI and the three high-resolution spectrometers of the A1 Collaboration,” emphasized Professor Josef Pochodzalla from the JGU Institute of Nuclear Physics. Researchers from Fudan University in Shanghai in China as well as from Tohoku University Sendai and the University of Tokyo in Japan were involved in the experiment.