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Researchers have succeeded in creating an efficient quantum-mechanical light-matter interface using a microscopic cavity. Within this cavity, a single photon is emitted and absorbed up to 10 times by an artificial atom. This opens up new prospects for quantum technology, report physicists at the University of Basel and Ruhr-University Bochum in the journal Nature.

Quantum physics describes photons as light particles. Achieving an interaction between a and a is a huge challenge due to the tiny size of the atom. However, sending the past the atom several times by means of mirrors significantly increases the probability of an interaction.

In order to generate photons, the researchers use artificial atoms, known as . These semiconductor structures consist of an accumulation of tens of thousands of atoms, but behave much like a single atom: when they are optically excited, their energy state changes and they emit a photon. “However, they have the technological advantage that they can be embedded in a ,” says Dr. Daniel Najer, who conducted the experiment at the Department of Physics at the University of Basel.

In the latest sign of growing interest in the flying taxi sector, United Airlines and air mobility startup Archer Aviation have announced an upcoming service for hops between downtown Chicago and O’Hare International Airport.

The service will offer a sustainable, low-noise, and cost-competitive alternative to ground transportation for folks traveling to and from the airport, United and Archer said in a release.

Could an injection of lab-cultured brain cells, created from a person’s own cells, reverse symptoms of Parkinson’s disease? That’s an idea that Aspen Neuroscience Inc., a startup based in San Diego, plans to test in human trials later this year.

In patients with Parkinson’s, neurons die and lose the ability to make the chemical dopamine, leading to erratic, uncontrollable movements. Aspen Neuroscience will test if the newly injected cells can mature into dopamine producers, stopping the debilitating symptoms of this incurable disease, says Damien McDevitt, the company’s chief executive officer. Tests in animals have shown promise, the company says.

Supercomputers and quantum computers are potent tools for handling difficult calculations, problem-solving, and data analysis. Although they both have the potential to transform computing technology, their speeds and capacities differ greatly.

Supercomputers quickly process massive volumes of data to provide a single result using a conventional computing strategy with numerous processors. These computers are the most powerful in terms of raw computing speed, but they can only do one task at a time, and Moore’s Law places a cap on how much data they can process (the principle that computer processor speeds double every two years).

Quantum computers, on the other hand, utilize laws of quantum mechanics to process information in ways that regular computers cannot, resulting in vastly higher processing speeds. They can manage several activities at once and take on challenging issues that would take supercomputer months to resolve. Yet, because of their great sensitivity to temperature fluctuations and need for isolation from outside influences, quantum computers require more upkeep than their conventional equivalents.

Researchers use an optical vortex beam to create a stable pattern of electron spins in a thin layer of semiconductor material.

Spin-based electronic, or “spintronic,” devices can benefit from techniques that coax electron spins into static spatial patterns called spin textures. A new experiment demonstrates that an optical vortex—a light beam that carries orbital angular momentum—can generate a stable spin texture in a semiconductor [1]. The research team showed that the vortex generates a pattern of stripes that has potential uses in processing spin information. Previous experiments have optically stimulated these striped textures, but the optical vortex has a structure that approximately overlaps with the stripe pattern, allowing faster spin-texture formation.

The spins of unbound electrons in a material can be aligned by a magnetic field or by polarized light. But as these electrons move—either through diffusion or through conduction—their spins will begin to rotate in response to so-called spin-orbit interactions within the material. The direction and rate of these rotations for any given electron depend on the path that it takes. Thus, two nearby electrons that start out aligned will become misaligned as they move along different paths, even if they arrive at the same destination. So maintaining an electronic spin texture seems like a doomed enterprise.

A white dwarf star can explode as a supernova when its mass exceeds the limit of about 1.4 solar masses. A team led by the Max Planck Institute for Extraterrestrial Physics (MPE) in Garching and involving the University of Bonn has now found a binary star system in which matter flows onto the white dwarf from its companion.

The system was found due to bright, so-called super-soft X-rays, which originate in the nuclear fusion of the overflowed gas near the surface of the white dwarf. The unusual thing about this source is that it is and not hydrogen that overflows and burns. The measured luminosity suggests that the mass of the white dwarf is growing more slowly than previously thought possible, which may help to understand the number of supernovae caused by exploding . The results have been published in the journal Nature.

Exploding white dwarfs are not only considered the main source of iron in the universe, they are also an important tool for cosmology. As so-called Type Ia supernovae (SN Ia), they all become roughly equally bright, allowing astrophysics a precise determination of the distance of their host galaxies.