Many natural processes, ranging from magnetism to chemical reactions, entail the movement and rotation of particles at very small scales. In quantum mechanics, particles exhibit both particle-like and wave-like behaviors, and their states can be described mathematically using representations known as wavefunctions.
Nearly 100 years ago, a seemingly simple discovery revolutionized the microscope. The introduction of phase contrast, which garnered a Nobel Prize in 1953, brought into clear view structures inside cells that had previously been too faint or washed out for biologists to study.
Stars shine because atoms fuse in their interiors, releasing energy. When a very massive star has exhausted its nuclear fuel, radiation pressure can no longer provide sufficient counterforce to gravity. The star then collapses under its own mass until only a single point remains: the singularity.
A drop of dye added to a glass of water undergoes ordinary diffusion. However, when placed on the surface of a foam, the dye spreads differently—diffusion becomes anomalous. An example of this is the pattern on the froth of a cup of cappuccino. Interestingly, recent research suggests that diffusion equations in a heterogeneous environment can also describe social phenomena, such as election results or the behavior of stock market traders. The study is published in the Chaos: An Interdisciplinary Journal of Nonlinear Science.
An international team whose research was coordinated by Osaka Metropolitan University (OMU) has reported the survival of metallic behavior in the strongly correlated molecular material ytterbium cesium fulleride (Yb₂CsC₆₀). The electrons in the newly synthesized material remained mobile and continued to conduct electricity even at the lowest temperatures studied, despite strong electron interactions that would normally be expected to drive the material into an insulating state.
In a quest to build the most accurate quantum sensors in the world, scientists are constantly improving their performance, making them more precise, more stable and more reliable. But eventually, physical constraints will prevent further improvements.
GaN-based vertical-cavity surface-emitting lasers (VCSELs) are promising for displays, sensing and optical communication, but improving efficiency remains challenging. Researchers have now shown that "cavity tuning," which controls resonance wavelength, strongly affects laser performance. By analyzing variations across a VCSEL wafer, the team identified optimal mirror loss conditions and extracted device parameters. Their approach achieved 26.4% wall plug efficiency, offering guidance for next-generation high-efficiency visible-light semiconductor lasers.
Quantum materials, materials with properties that are governed by the laws of quantum mechanics, have proved to be highly promising for the development of ultra-efficient electronic devices, quantum processors, highly precise sensors and various other technologies. Reliably controlling these materials' quantum phases would be highly advantageous, as it would enable engineers to tailor and optimize their properties for specific applications.
Birds in flocks, bacteria and cells: In many collective systems, individual elements respond to only part of their surroundings, seemingly defying Newton's third law of motion—action equals reaction. These exceptions are known as nonreciprocal interactions. A Dresden physics team working with Roderich Moessner, a founding member of the Würzburg–Dresden Cluster of Excellence ctd.qmat, has now developed a theory that makes it possible to describe these interactions efficiently and simulate them far more precisely.
Two independent research teams have achieved a longstanding goal in physics: building a working nuclear clock. The devices, developed by Beichen Huang and colleagues at Tsinghua University and by Luca Toscani De Col and colleagues at the Vienna Center for Quantum Science and Technology in Austria, exploit the nucleus of a thorium-229 atom to keep time with extraordinary precision—possibly surpassing even the best atomic clocks available today.
A University of Birmingham scientist has built a "mini-universe" that takes a step toward answering one of science's biggest questions: "What is time?" Publishing his findings in Physical Review Research, Professor Giovanni Barontini shows how it is possible to measure the flow of time without using a clock at all. The new findings provide a scientific model in which a version of time emerges from the experiment itself.
A recent study published in Nature Communications demonstrates precise control over electron spatial arrangement in two directions simultaneously—without any applied voltage—through interface engineering between semimetal bismuth (Bi) thin films and two-dimensional semiconductor MoS₂.
A team of researchers has leveraged a supercomputer at the U.S. Department of Energy's (DOE) Argonne National Laboratory to reveal the internal structure of a pion in unprecedented detail. The findings are published in the Journal of High Energy Physics.
In the next few decades, many physicists are hopeful that nuclear fusion could become a realistic source of practically limitless energy. But before this can happen, it will be critical to ensure that reactors cannot be covertly misused to produce materials for nuclear weapons.
Pack enough string-like objects together, and they will begin to align with one another. But replace the strings with worms or bacteria living in your gut, and this self-organization becomes much more difficult. A team of University of Amsterdam (UvA) researchers has demonstrated that activity can fundamentally alter one of the most important phase transitions in soft matter physics.
---- End of list of PHYS ORG Physics Articles on this page 2 of 2 total pages ----