Related papers: Feedback Induced Magnetic Phases in Binary Bose-Ei…
For many physical systems which can be approximated by a classical background field plus small (linearized) quantum fluctuations, a fundamental question concerns the correct description of the backreaction of the quantum fluctuations onto…
Spinor Bose Einstein condensates (BEC) can be realized nowadays using different atomic species of several spin values, offering unprecedented opportunities to scrutinize the underlying physics of its spin phase domains and of its quantum…
Controlling a quantum system based on the observation of its dynamics is inevitably complicated by the backaction of the measurement process. Efficient measurements, however, maximize the amount of information gained per disturbance…
By improving the Bose-Einstein condensate model of dark matter through the repulsive three-particle interaction to better reproduce observables such as rotation curves, both different thermodynamic phases and few-particle correlations are…
Spin-orbit coupled Bose-Einstein condensates (BECs) provide a powerful tool to investigate interesting gauge-field related phenomena. We study the ground state properties of such a system and show that it can be mapped to the well-known…
So far the theory of Bose-Einstein condensates (BEC) of polar molecules was based on an ad hoc generalization of equations for spherical atoms. Here I adopt a rigorous pseudo-potential approach to low-energy dipolar interactions and derive…
We consider the fate of Bose-Einstein condensation (BEC) with time-reversal symmetry and inversion symmetry in a spin-orbit coupled bilayer system. When these two symmetry operators commute, all the single particle bands are exactly…
We study tunneling processes of Bose-Einstein condensate (BEC) on the real time stochastic approach and reveal some properties of their tunneling time. An important result is that the tunneling time decreases as the repulsive interatomic…
The quantum limits of stochastic cooling of trapped atoms are studied. The energy subtraction due to the applied feedback is shown to contain an additional noise term due to atom-number fluctuations in the feedback region. This novel effect…
We study the dynamic behavior of a Bose-Einstein condensate (BEC) with dipolar interactions when the influence of external electric fields affects the coherent tunneling properties. Here, we propose a tunable platform based on BECs where…
Our understanding of various states of matter usually relies on the assumption of thermodynamic equilibrium. However, the transitions between different phases of matter can be strongly affected by non-equilibrium phenomena. Here we…
We apply the technique of reinforcement learning to the control of nonlinear matter waves. In this method, an agent controls the position, strength, and shape of an external Gaussian potential to create and manipulate quantized vortices in…
We report on measurements of the excitation spectrum of a strongly interacting Bose-Einstein condensate (BEC). A magnetic-field Feshbach resonance is used to tune atom-atom interactions in the condensate and to reach a regime where quantum…
The dynamics of a quantum anharmonic oscillator whose position is monitored by a Bose-Einstein condensate (BEC) trapped in a symmetric double well potential is studied. The (non-exponential) decoherence induced on the oscillator by the…
By recognizing the vital importance of two-hole Cooper pairs (CPs) in addition to the usual two-electron ones in a strongly-interacting many-electron system, the concept of CPs was re-examined with striking conclusions. Based on this,…
We consider a Bose-Einstein condensate driven by periodic delta-kicks. In contrast to first-order descriptions, which predict rapid, unbounded growth of the noncondensate in resonant parameter regimes, the consistent treatment of condensate…
We solve a model that describes a stimulated conversion between ultracold bosonic atoms and molecules. The reaction is triggered by a linearly time-dependent transition throughout the Feshbach resonance. Our solution predicts a…
The resonant dynamics of mediated interactions supports zero-sound in a cold atom degenerate mixture of a single component fermion gas and a Bose-Einstein condensate (BEC). We characterize the onset of instability in the phase separation of…
The resonant formation of nonlinear coherent modes in trapped Bose-Einstein condensates is studied. These modes represent nonground-state Bose condensates. The methods of describing the spectrum of the nonlinear modes are discussed. The…
We have studied theoretically the basic operation of a quantum feedback loop designed to maintain the desired phase of quantum coherent oscillations in a two-level system. Such feedback can suppress the dephasing of oscillations due to…