Dynamics of spatial phase coherence in a dissipative Bose-Hubbard atomic system

Abstract

We investigate the loss of spatial coherence of one-dimensional bosonic gases in optical lattices illuminated by a near-resonant excitation laser. Because the atoms recoil in a random direction after each spontaneous emission, the atomic momentum distribution progressively broadens. Equivalently, the spatial correlation function (the Fourier-conjugate quantity of the momentum distribution) progressively narrows down as more photons are scattered. Here we measure the correlation function of the matter field for fixed distances corresponding to nearest-neighbor (n-n) and next-nearest-neighbor (n-n-n) sites of the optical lattice as a function of time, hereafter called n-n and n-n-n correlators. For strongly interacting lattice gases, we find that the n-n correlator $C_1$ decays as a power-law at long times, $C_1\propto 1/t^{\alpha }$, in stark contrast with the exponential decay expected for independent particles. The power-law decay reflects a non-trivial dissipative many-body dynamics, where interactions change drastically the interplay between fluorescence destroying spatial coherence, and coherent tunnelling between neighboring sites restoring spatial coherence at short distances. The observed decay exponent $\alpha \approx 0.54(6)$ is in good agreement with the prediction $\alpha =1/2$ from a dissipative Bose-Hubbard model accounting for the fluorescence-induced decoherence. Furthermore, we find that the n-n correlator $C_1$ controls the n-n-n correlator $C_2$ through the relation $C_2\approx C_1^2$, also in accordance with the dissipative Bose-Hubbard model.

published in the special issue of Comptes Rendus Physique dedicated to Jean Dalibard's CNRS Gold Medal. Details of calculations, included as an appendix in the published article, are available in the ancillary file

References in corpus (21)

• Many-Body Physics with Ultracold Gases
• The physics of dipolar bosonic quantum gases
• One dimensional Bosons: From Condensed Matter Systems to Ultracold Gases
• Transition from a strongly interacting 1D superfluid to a Mott insulator
• Bragg spectroscopy of a Bose-Einstein condensate
• Exploring phase coherence in a 2D lattice of Bose-Einstein condensates
• Universally valid reformulation of the Heisenberg uncertainty principle on noise and disturbance in measurement
• Violation of Heisenberg's Measurement-Disturbance Relationship by Weak Measurements
• Proof of Heisenberg's error-disturbance relation
• Expansion of a coherent array of Bose-Einstein condensates
• Non-equilibrium dynamics of bosonic atoms in optical lattices: Decoherence of many-body states due to spontaneous emission
• Quantum Control by Imaging : The Zeno effect in an ultracold lattice gas
• Non-Hermitian Linear Response Theory
• Interaction-induced impeding of decoherence and anomalous diffusion
• Anomalous momentum diffusion in a dissipative many-body system
• Emergence of glass-like dynamics for dissipative and strongly interacting bosons
• Measuring measurement--disturbance relationships with weak values
• Heating rates for an atom in a far-detuned optical lattice
• Clock spectroscopy of interacting bosons in deep optical lattices
• Doppler Spectroscopy of an Ytterbium Bose-Einstein Condensate on the Clock Transition
• Heating from Continuous Number Density Measurements in Optical Lattices

Cited by in corpus (2)

• Many-Body Open Quantum Systems
• Exact density profile in a tight-binding chain with dephasing noise