Physicists build an atom laser that can stay on forever

Phys.org  June 14, 2022 Bose–Einstein condensates (BECs) are important to quantum simulation and sensing. A long-standing constraint for quantum gas devices has been the need to execute cooling stages time-sequentially, restricting these devices to pulsed operation. Researchers in the Netherlands demonstrated continuous Bose–Einstein condensation by creating a continuous-wave (CW) condensate of strontium atoms that lasts indefinitely. The coherent matter wave is sustained by amplification through Bose-stimulated gain of atoms from a thermal bath. By steadily replenishing this bath while achieving 1,000 times higher phase-space densities than previous works they maintained the conditions for condensation. Their experiment is the matter wave […]

Researchers achieve quantum advantage

Phys.org  December 9, 2020 An on-demand and truly scalable source of indistinguishable single photons is the essential component enabling high-fidelity photonic quantum operations. A main challenge is to overcome noise and decoherence processes to reach the steep benchmarks on generation efficiency and photon indistinguishability required for scaling up the source. An international team of researchers (Denmark, Germany) has developed a single-photon source featuring near-unity indistinguishability using a quantum dot in an “on-chip” planar nanophotonic waveguide circuit. The device produces long strings of >100 single photons without any observable decrease in the mutual indistinguishability between photons. They were able to generate […]

A Metal-like Quantum Gas: A pathbreaking platform for quantum simulation

EurekAlert  June 22, 2020 Electronic properties of condensed matter are often determined by an intricate competition between kinetic energy that aims to overlap and delocalize electronic wave functions across the crystal lattice, and localizing electron-electron interactions. In contrast, the gaseous phase is characterized by valence electrons tightly localized around the ionic atom cores in discrete quantum states with well-defined energies. A hybrid state of matter is created when a gas of isolated atoms is suddenly excited to a state where electronic wave functions spatially overlap like in a solid. Researchers in Japan created such a hybrid state with overlapping high-lying electronic […]

In a new quantum simulator, light behaves like a magnet

Phys.org  March 19, 2019 An international team of researchers (Switzerland, France, Japan) proposes a new “quantum simulator”, a photonic device that can be built and run with current experimental techniques. It may be built using superconducting coupled to laser fields in such a way that it causes an effective interaction among photons. It can simulate the complex behavior of real, interacting magnets at very low temperatures. They found that the photons behaved in the same way as magnetic dipoles across the quantum phase transition in real materials. The Using the new technique photons can be used to run a virtual […]

D-Wave demonstrates first large-scale quantum simulation of topological state of matter

Eurekalert  August 22, 2018 Researchers in Canada demonstrated a large-scale quantum simulation of this phenomenon in a network of 1,800 in situ programmable superconducting niobium flux qubits whose pairwise couplings are arranged in a fully frustrated square-octagonal lattice. They observed the emergence of a complex order parameter with continuous rotational symmetry, and the onset of quasi-long-range order as the system approaches a critical temperature. According to the researchers the approach of using a quantum processor as a programmable magnetic lattice will find widespread use in the simulation and development of exotic materials…read more.  TECHNICAL ARTICLE