Two Cold Atoms in a Harmonic Trap
Two ultracold atoms moving in a trap interact weakly at a very short distance. This interaction can be modeled by a properly regularized contact potential. We solve the corresponding time-independent…
Dark-bright solitons in inhomogeneous Bose-Einstein condensates.
It is shown that spatial inhomogeneity strongly affects dark-bright vector solitary wave solutions to the coupled nonlinear Schrödinger equations which describe an inhomogeneous two-species Bose-Einstein condensate, and that current technology suffices for their creation and control in ultracold trapped gases.
Orthogonality catastrophe as a consequence of qubit embedding in an ultracold Fermi gas
We investigate the behavior of a two-level atom coupled to a one-dimensional, ultracold Fermi gas. The sudden switching on of the scattering between the two entities leads to the loss of any…
Measurement of collective excitations in a spin-orbit-coupled Bose-Einstein condensate
We measure the collective excitation spectrum of a spin-orbit-coupled Bose-Einstein condensate using Bragg spectroscopy. The spin-orbit coupling is generated by Raman dressing of atomic hyperfine…
Negative-Mass Hydrodynamics in a Spin-Orbit-Coupled Bose-Einstein Condensate.
An expanding spin-orbit coupled Bose-Einstein condensate whose dispersion features a region of negative effective mass is measured, observing a range of dynamical phenomena, including the breaking of parity and of Galilean covariance, dynamical instabilities, and self-trapping.
Fast quasiadiabatic dynamics
We work out the theory and applications of a fast quasiadiabatic approach to speed up slow adiabatic manipulations of quantum systems by driving a control parameter as near to the adiabatic limit as…
Dynamics and energy spectra of aperiodic discrete-time quantum walks.
- N. Lo Gullo, C. V. Ambarish, T. Busch, L. Dell'Anna, C. M. Chandrashekar
- MathematicsPhysical Review E
- 14 November 2016
The energy spectra and the spreading of an initially localized wave packet for different cases are studied, finding that in the case of Fibonacci and Thue-Morse tilings the system is superdiffusive, whereas in the Rudin-Shapiro case it is strongly subdiffusive.
Non-Markovianity criteria for open system dynamics
A universal definition of non-Markovianity for open systems dynamics is proposed. It is extended from the classical definition to the quantum realm by showing that a `transition' from the Markov to…
Deep-learning-based quantum vortex detection in atomic Bose–Einstein condensates
- F. Metz, J. Polo, Natalya Weber, T. Busch
- PhysicsMachine Learning: Science and Technology
- 24 December 2020
This work introduces a machine-learning-based vortex detector motivated by state-of-the-art object detection methods that can accurately locate vortices in simulated BEC density images and allows for robust and real-time detection in noisy and non-equilibrium configurations.
Mimicking the probability distribution of a two-dimensional Grover walk with a single-qubit coin.
A formal proof of this correspondence is presented and the behavior of the coin-position entanglement as well as the x-y spatialEntanglement in the scheme with respect to the Grover one is analyzed.