Category Physics

Metasurfaces could be the next quantum information processors

In the race toward practical quantum computers and networks, photons hold intriguing possibilities as fast carriers of information at room temperature.

Photons are typically controlled and coaxed into quantum states via waveguides on extended microchips, or through bulky devices built from lenses, mirrors, and beam splitters. The photons become entangled—enabling them to encode and process quantum information in parallel—through complex networks of these optical components. But such systems are notoriously difficult to scale up due to the large numbers and imperfections of parts required to do any meaningful computation or networking.

Could all those optical components be collapsed into a single, flat, ultra-thin array of subwavelength elements that control light in the exac...

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Superheated gold withstands ‘entropy catastrophe’: New method challenges established physics

Researchers at SLAC’s Matter in Extreme Conditions (MEC) instrument used a laser to superheat a sample of gold. Then, they sent a pulse of ultrabright X-rays from the Linac Coherent Light Source (LCLS) through the sample to measure the speed, and thus the temperature, of the atoms vibrating in the sample.

Researchers at SLAC’s Matter in Extreme Conditions (MEC) instrument used a laser to superheat a sample of gold. Then, they sent a pulse of ultrabright X-rays from the Linac Coherent Light Source (LCLS) through the sample to measure the speed, and thus the temperature, of the atoms vibrating in the sample.

Researchers taking the first-ever direct measurement of atom temperature in extremely hot materials inadvertently disproved a decades-old theory and upended our understanding of s...

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Quantum internet moves closer as researchers teleport light-based information

Study demonstrates quantum teleportation from telecom photons to an erbium ion-based quantum memory
Quantum teleportation from telecom photons to erbium-ion ensembles. Credit: Group of Prof. Xiao-Song Ma at Nanjing University.

Quantum teleportation is a fascinating process that involves transferring a particle’s quantum state to another distant location, without moving or detecting the particle itself. This process could be central to the realization of a so-called “quantum internet,” a version of the internet that enables the safe and instant transmission of quantum information between devices within the same network.

Quantum teleportation is far from a recent idea, as it was experimentally realized several times in the past. Nonetheless, most previous demonstrations utilized frequency conversion rather than natively operating in the telecom band.

Researchers at Nanjing Univer...

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Scientists successfully develop half metal material that conducts single-spin electrons

The world's first 2D half metal created at Forschungszentrum Jülich
Two atoms thick layer of iron and palladium (left, yellow/red): Experiments with spin-resolved momentum microscopy show that only electrons with a specific spin direction (indicated as red/blue) can be found on the so-called Fermi surface and thus actively contribute to charge transport. Credit: Forschungszentrum Jülich / Xin Liang Tan

Researchers at Forschungszentrum Jülich have successfully created the world’s first experimentally verified two-dimensional half metal—a material that conducts electricity using electrons of just one spin type: either “spin-up” or “spin-down.” Their findings, now published as an Editors’ Suggestion in Physical Review Letters, mark a milestone in the quest for materials enabling energy-efficient spintronic that go beyond conventional electronics.

H...

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