Nonlinearity of quantum dot waveguide helps entangle photons

European physicists have studied in detail the interaction of single photons in a photonic crystal waveguide containing a quantum dot. They showed that by varying the duration of the pulses and their delay, it is possible to achieve varying degrees of nonlinearity, as well as control the degree of correlation of light quanta. The study… Continue reading Nonlinearity of quantum dot waveguide helps entangle photons

Metasurfaces emit entangled photons with variable wavelengths

American and German physicists have fabricated thin metasurfaces consisting of arrays of silicon nanocavities that exhibit spontaneous parametric scattering. They showed that such structures are capable of generating entangled photons. Unlike traditional media used for this, metasurfaces have greater flexibility, which allows the wavelength of the resulting photons to be changed by changing the pump… Continue reading Metasurfaces emit entangled photons with variable wavelengths

An antilaser with a degenerate cavity turned out to be an excellent absorber

Physicists combined the idea of ​​a coherent ideal absorber (antilaser) with the concept of a degenerate resonator. The constructed optical system effectively absorbs light incident on it from various angles, and its operation has proven to be resistant to typical interference in optical communication lines. The study was published in Science. Absorption is an important… Continue reading An antilaser with a degenerate cavity turned out to be an excellent absorber

Physicists made photons interfere with magnons

Chinese physicists have demonstrated quantum interference between waves of different natures, namely between photons and magnons. They repeated the Hong-Wu-Mandel experiment, where dark polaritons excited in an atomic cloud acted as a beam splitter. By controlling the properties of polaritons using an additional laser, scientists could change the nature of the interference from bosonic to… Continue reading Physicists made photons interfere with magnons

Physicists have learned to control the asymmetrical interaction of levitating particles

Physicists using laser tweezers have learned to control the interaction between two bound levitating nanoparticles that act on each other with different forces. By changing the parameters of the laser beam, scientists controlled the position of the particles, the amplitude and phase of their oscillations, and the force of interaction. The method will make it… Continue reading Physicists have learned to control the asymmetrical interaction of levitating particles

A candidate for an artificial radio signal from an Earth-like exoplanet turned out to be of terrestrial nature

Astronomers have concluded that the unusual narrow-band radio signal recorded in the direction of the Kepler-438 exoplanet system last year by the FAST telescope is not a technosignature, but is of anthropogenic origin. This is indicated by the polarization properties of the signal. A preprint of the work was published on arXiv.org. To answer the… Continue reading A candidate for an artificial radio signal from an Earth-like exoplanet turned out to be of terrestrial nature

Physicists have implemented optical stochastic cooling of particle beams

American physicists reported that they were the first to realize optical stochastic cooling of beams of charged particles. This type of cooling consists of damping pulse fluctuations through a feedback system. In the new work, this communication occurred at optical frequencies, which is necessary to increase the efficiency and cooling rate of accelerators and synchrotrons.… Continue reading Physicists have implemented optical stochastic cooling of particle beams

The speed of interaction of Rydberg qubits has been brought closer to the fundamental limit

Japanese physicists have succeeded in achieving energy exchange between qubits based on Rydberg atoms on a nanosecond scale, approaching the fundamental limit of this platform. In the future, this will allow quantum computing to be performed faster than decoherence destroys the states of qubits. The study was published in Nature Photonic. Despite the wide variety… Continue reading The speed of interaction of Rydberg qubits has been brought closer to the fundamental limit

Physicists capture neutral atoms using metalens

American physicists have produced a silicon metalens for the needs of optical tweezers and lattices. The created sample is only slightly inferior in characteristics to its traditional counterparts, but is much more compact than them. In addition, the new optical element not only focuses light to create an optical lattice, but also collects the fluorescence… Continue reading Physicists capture neutral atoms using metalens

Specialized itch neurons found in rat brains

Chinese biologists have found that in the brain of rats there are two populations of neurons that practically do not overlap. Some respond only to painful stimuli, others only to pruritogens (substances that cause itching). This means that – at least at the level of the ventrolateral zone of the orbitofrontal cortex – itch can… Continue reading Specialized itch neurons found in rat brains