Abstract: Method and apparatus for quantum simulation, based on a linear chain of ions. A gradient field is imposed to break the symmetry of the ion chain, and bichromatic driving fields are applied to bridge the energy gaps induced by the gradient field and thereby establish resonance couplings among the ions according to their relative positions in the gradient field. The combination of the gradient field and the bichromatic driving fields implement excitation hopping to simulate a variety of topologies according to higher¬dimensional Hamiltonians and boundary conditions, including ring, torus, Mobius strip configurations, as well as topologies with periodic boundary conditions. In particular synthetic gauge fields allow simulation of magnetic flux.

Abstract: Provided is a quantum computing device comprising a carbon nanotube, a superconducting substrate in quantum proximity to the nanotube and being in a superconducting state having a pairing correlation matrix with a substantial spin-triplet component in a direction perpendicular to the nanotube, and a magnet arranged to provide a longitudinal magnetic field along a longitudinal axis of the nanotube. Further provided is a quantum computing device comprising at least three substrates made of a superconductor material and each in a superconducting state, and a non-superconducting structure made of a material in which the electrons' closed trajectories experience strong spin-orbit coupling interactions and being in quantum proximity to the substrates. The sum of the phase differences between the order parameters of all of the substrates is at least ?.

Abstract: An atomic vector magnetometer and magnetometric methods based on atomic clock transitions unaffected by magnetic field strength for increased quantum coherency time, resulting in improved sensitivity over conventional Zeeman-based atomic magnetometry, where coherency is restricted by sensitivity to magnetic fields. Instead of measuring magnetic field strength in the direction of the quantization axis, as in Zeeman magnetometry, magnetic field strength is measured substantially orthogonal to the quantization axis, via determining the angular displacement of the quantization axis by the magnetic signal field, which is detected by changes in atomic state populations as the quantization axis is rotated relative to the excitation polarization. In addition, the present invention measures magnetic fields instantaneously rather than via accumulated phase shift over time, as in Zeeman magnetometry, thereby providing measurement and spectral analysis of time-varying magnetic fields.