Microscopic dynamics of ultracold particles in a ring-cavity optical lattice

Abstract

The quantum dynamics of particles optically trapped in a symmetrically pumped high-Q ring cavity exhibits much richer physics than for a standing-wave resonator. In addition to modifying the lattice depth, light scattering by the particles shifts and reshapes the trapping potential. We calculate the corresponding changes in tunneling amplitudes and damping by an effective bipotential (two-level) model for the particle motion. As a crude truncation of the Bose-Hubbard model, expansion to the lowest band decouples particle and field dynamics. Only including excitations to higher bands can capture this essential additional physics and correctly describe decoherence, damping, and long-range correlations of the particle dynamics. The validity limits of the analytic models are confirmed by quantum Monte Carlo wave-function simulations, which exhibit correlated particle-field quantum jumps as unambiguous quantum signature of the system dynamics.

Quantum optics with ultracold quantum gases: towards the full quantum regime of the light–matter interaction

“…The tunneling dynamics in quantum optical lattices was analyzed in [12,[77][78][79]. A fundamental difference of the quantum lattices from their classical analogues is that the coupling of atoms to the leaking light mode opens a new dissipation channel for atomic dynamics.…”

Cavity-induced chiral states of fermionic quantum gases

“…In such a setup, a modified Bose-Hubbard model of the bosonic quantum gas can be reached and the influence of cavity-induced, longrange interactions between the atoms onto the superfluid to Mott-insulator phase transition has been investigated [6,[25][26][27][28][29][30][31][32].…”

Tunneling dynamics of bosonic Josephson junctions assisted by a cavity field

“…The optical potential created by the cavity photons alters significantly the external trapping potential, which modifies the atomic motion and thus the dispersive medium where the photon field propagates. The parameters of the low-energy description of the atomic motion become dependent on the state of the photon field being itself a dynamic quantity [18][19][20][21][22][23][24][25]. Addition of an optical resonator to the double-well setup therefore leads to a hybrid system where some or all of the bosonic Josephson-junction (BJJ) parameters become dynamical quantities.…”