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

Physicists have proven the importance of the mesoscale for quantum phase transitions

Low-temperature phase transitions in ferromagnets are characterized by destruction of the domain structure. In an article in Nature physicists write that for a theoretical description of the dynamics of such transitions, it is necessary to take into account not only microscopic, but also mesoscale symmetry. This discovery indicates the possibility of the existence of non-classical… Continue reading Physicists have proven the importance of the mesoscale for quantum phase transitions

Physicists were able to obtain acoustic frequency combs at 10 gigahertz

American physicists have manufactured a hybrid system from a nonlinear oscillatory circuit and an acoustic resonator connected by a piezoelectric contact. This combination made it possible to impart nonlinearity to acoustic modes at a frequency of 10 gigahertz. The authors were able to generate coherent acoustic frequency combs in their setup, which will help combat… Continue reading Physicists were able to obtain acoustic frequency combs at 10 gigahertz

Mirror light nuclei differed from heavy ones in the frequency of nucleon pair production

Physicists from 13 countries presented the results of a study of the relative frequency of production of short-range two-nucleon correlations in the lightest mirror nuclei containing three nucleons. The data were obtained for a certain kinematic range during electron scattering by nuclei. The collaboration found that in light nuclei, neutron-proton pairs are formed approximately twice… Continue reading Mirror light nuclei differed from heavy ones in the frequency of nucleon pair production

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

One atom emits fourteen entangled photons

German physicists have reported the successful generation of entangled multiqubit states on photons using a single atom placed in a cavity. They managed to involve 12 photons in the creation of cluster states, and 14 photons of Greenberger-Horn-Zeilinger states. The frequency of generation and detection of entangled photonic chains based on the proposed scheme turned… Continue reading One atom emits fourteen entangled photons

Machine learning predicts the thickness of lead's neutron skin

Physicists have calculated the thickness of the neutron shell in the core of the lead-208 isotope – it is in the range from 0.14 to 0.20 femtometers. To do this, scientists combined calculations from first principles, statistical methods and machine learning. This scheme works faster than direct simulations and in the future it can be… Continue reading Machine learning predicts the thickness of lead's neutron skin