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Conventional curved lenses, which direct light by refraction in glass or plastic, are often bulky and heavy, offering only limited control of light waves. Metasurfaces, in contrast, are flat and consist of an array of tiny structures known as meta-atoms. Meta-atoms influence light at a subwavelength scale and thus allow for highly precise control of the phase, amplitude, and polarization of light.

“Using metasurfaces, we can influence the temporal shift, intensity, and direction of oscillation of light waves in a targeted way,” says Dr. Maryna Leonidivna Meretska, Group Leader at KIT’s Institute of Nanotechnology.

“Thanks to its multiplex control capabilities, i.e., the simultaneous and targeted influencing of various parameters, a single metasurface can replace multiple . Thus, the size of the optical system can be reduced without affecting its performance.”

A revolutionary new spintronic device developed in China enables powerful, precise control of terahertz (THz) wave polarization, without the need for bulky external components. Using a clever microscale stripe design, the compact emitter manipulates the chirality of THz waves at the source, allow

After 25 years of smashing gold nuclei together at light speeds, Brookhaven National Laboratory’s Relativistic Heavy Ion Collider is hanging up its boots—erm, superconducting magnets.

The collider’s final run—its 25th—kicked off this week on Long Island, in a swan song for the venerable collider that will be succeeded—in fact, transformed into—Brookhaven Lab’s Electron-Ion Collider (EIC). Over the course of 2025, RHIC physicists will complete data collection on quark-gluon plasma, the soup of particles that existed in the earliest days of the universe.

“The original idea behind RHIC was to create, for the first time on Earth, a state of matter that existed in the universe a few microseconds after the Big Bang: the quark-gluon plasma, and we did,” said James Dunlop, the associate department chair for nuclear physics at Brookhaven Lab, in a call with Gizmodo. “That’s one of the big legacies—that we actually created it—but the more interesting thing is that its properties were quite different from what we’d expected them to be.”

This Quantum Computer Simulates the Hidden Forces That Shape Our Universe

The study of elementary particles and forces is of central importance to our understanding of the universe. Now a team of physicists from the University of Innsbruck and the Institute for Quantum Computing (IQC) at the University of Waterloo show how an unconventional type of quantum computer opens a new door to the world of elementary particles.

Credit: Kindea Labs

Studies that explore how the denser sections of atoms, known as atomic nuclei, interact with neutrons (i.e., particles with no electric charge) can have valuable implications both for the understanding of these atoms’ underlying physics and for the development of nuclear energy solutions. A process that is central to these interactions is neutron capture, which entails the absorption of a neutron by a nucleus, followed by the emission of gamma-rays.

Researchers at Los Alamos National Laboratory recently carried out a study aimed at better understanding the origin of the exceptional neutron capture capabilities of the zirconium-88 (88 Zr), using a new experimental methodology. Their findings, published in Physical Review Letters, offer valuable insight that could help to improve existing nuclear and astrophysical models.

“The probability (per unit area) of a nucleus capturing a neutron at a given kinetic energy is called neutron-capture cross section,” Thanos Stamatopoulos, first author of the paper, told Phys.org. “The probability across several kinetic energies from 0.5 eV up to infinity is called resonance integral. Typically, in nature, when the cross section for neutrons with a kinetic energy of 25 meV (thermal cross section) is very large, the resonance integral is small.”

Photovoltaic (PV) solutions, which are designed to convert sunlight into electrical energy, are becoming increasingly widespread worldwide. Over the past decades, engineers specialized in energy solutions have been trying to identify new solar cell designs and PV materials that could achieve even better power conversion efficiencies, while also retaining their stability and reliably operating for long periods of time.

The many emerging PV solutions that have proven to be particularly promising include tandem based on both perovskites (a class of materials with a characteristic crystal structure) and organic materials. Perovskite/organic tandem solar cells could be more affordable than existing silicon-based solar cells, while also yielding higher power conversion efficiencies.

These solar cells are manufactured using wide-bandgap perovskites, which have an electronic bandgap greater than 1.6 electronvolts (eV) and can thus absorb higher-energy photons. Despite their enhanced ability to absorb high-energy light particles, these materials have significant limitations, which typically adversely impact the stability of solar cells.

Researchers from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences revealed that not all forms of quantum nonlocality guarantee intrinsic randomness. They demonstrated that violating two-input Bell inequalities is both necessary and sufficient for certifying randomness, but this equivalence breaks down in scenarios involving multiple inputs. The study is published in Physical Review Letters.

Quantum mechanics is inherently probabilistic, and this intrinsic has been leveraged for applications like random number generation. However, ensuring the security of these random numbers in real-world scenarios is challenging due to potential vulnerabilities in the devices used.

Bell nonlocality, where particles exhibit correlations that cannot be explained by classical physics, offers a way to certify randomness without trusting the devices. Previous studies have shown that violating Bell inequalities can certify randomness in simple two-input, two-output systems. However, the applicability of this principle to more complex, multiple-input, multiple-output (MIMO) systems has been unclear.

In a new paper, researchers at North Carolina State University show proof of concept for a system that—in a single cycle—actively removes microplastics from water.

The findings, described in the journal Advanced Functional Materials, hold the potential for advances in cleansing oceans and other bodies of water of tiny plastics that may harm human health and the environment.

“The idea behind this work is: Can we make the cleaning materials in the form of soft particles that self-disperse in water, capture microplastics as they sink, and then return to the surface with the captured microplastic contaminants?” said Orlin Velev, the S. Frank and Doris Culberson Distinguished Professor of Chemical and Biomolecular Engineering at NC State and corresponding author of the paper.