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

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

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

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 have experimentally confirmed quantum pseudotelepathy

Chinese physicists experimentally played the Mermin-Perez quantum game using hyperentangled photons. This game is an example of quantum pseudo-telepathy, that is, a game in which a quantum solution gives, in theory, a 100% guarantee of success. In practice, scientists won in 94 cases out of 100 due to noise and imperfections in the optical design,… Continue reading Physicists have experimentally confirmed quantum pseudotelepathy

White storks give up migrating to Africa to live in Spanish landfills

White storks have long stopped in Spain during their autumn migration to Africa. However, now many of them complete their journey here. Instead of continuing their flight, they spend the entire winter in Spanish landfills, feeding on garbage. In addition to the abundance of food, climate change contributes to this – winters on the Iberian… Continue reading White storks give up migrating to Africa to live in Spanish landfills

Theorists have solved quantum communication at interstellar distances

British theorists studied in detail the influence of the interstellar and circumstellar medium on the possibility of quantum communications at such long distances and came to the conclusion that such communication is possible. They showed that X-ray radiation is best suited for this, and the quantum signal itself can become a good marker of an… Continue reading Theorists have solved quantum communication at interstellar distances

Chirality of molecules revealed using twisted X-rays

European physicists were able to measure the vortex dichroism signal of a molecular complex using twisted X-rays. To do this, they passed x-rays through spiral zone plates with different topological charges. This method allows one to study the chirality of molecules more accurately than methods based on circular dichroism. The study was published in Nature… Continue reading Chirality of molecules revealed using twisted X-rays