Dissipative dynamics and cooling rates of trapped impurity atoms immersed in a reservoir gas

Abstract

We study the dissipative dynamics of neutral atoms in anisotropic harmonic potentials, immersed in a reservoir species that is not trapped by the harmonic potential. Considering initial motional excitation of the atoms along one direction, we explore the resulting spontaneous emission of reservoir excitations, across a range of trap parameters from strong to weak radial confinement. In different limits these processes are useful as a basis for analogies to laser cooling, or as a means to introduce controlled dissipation to many-body dynamics. For realistic experimental parameters, we analyse the distribution of the atoms during the decay and determine the effects of heating arising from a finite temperature reservoir.

Non-Markovian Quantum Dynamics in Strongly Coupled Multimode Cavities Conditioned on Continuous Measurement

“…New schemes for quantum information processing and production of entanglement [32] could also be investigated, exploiting the higher coherence achievable in the strong-coupling regime, the use of different cavity modes to realize quantum gates (or conversely the use of the atoms to realize quantum gates between photonic qubits [104,105]), or the potential of using the feedback formalism to implement error correction protocols. Finally, it is important to stress again that while we use the language of optical cavity QED, the underlying model is universal and can equally be applied to plasmonic cavities [40], cold atoms reservoirs [37][38][39], electron-phonon systems [36], or circuit QED [33,35]. Given the high cooperativity achievable in this latter platform, we expect our formalism to be indeed particularly useful for exploring control and readout of superconducting qubits.…”

“…Although for concreteness we discuss the example of cavity QED, our theory can be applied to arbitrary quantum systems coupled to a non-Markovian bath which can be split into two parts with a larger Markovian open system in front of the detector. This includes networks of standard single-mode cavity QED, coupled resonator ar-rays and circuit QED [33][34][35], systems of electrons coupled to damped phonons (i.e., a dissipative Hubbard-Holstein model [36]) relevant for the solid-state, systems of cold atoms immersed in a BEC [37] or coupled coherently to an untrapped level [38,39], or quantum emitters coupled to plasmonic cavities [40] which can be modeled in terms of leaky quasinormal modes [41].…”

Dynamics of a trapped ion in a quantum gas: effects of particle statistics

“…In conclusion, the ion master equation like the ones for a neutral impurity in a condensate [45,46,59] cannot be recasted in Lindblad form, unless the counter rotating terms are neglected. In the future, however, it would be interesting to explore another approach that has been recently proposed [62].…”

“…not superfluid BCS theory, and it is obtained as a special case of the master equation for a bosonic bath for gas temperatures above the critical temperature of condensation. We note that in the literature a master equation treatment of an impurity in a degenerate Bose gas has already been undertaken [31,[45][46][47], but (i) only the (linear) Fröhlich interaction has been considered and (ii) the Lamb-shift have been not taken into account. Moreover and specifically for the ionic impurity, the fermionic bath has been not investigated in Ref.…”

“…( 56) in Lindbland form (see also appendix F), as an essential requisite is the RWA [56]. We note that up until now, these effects have been not taken into account in investigations in the context of impurity physics for settings similar to ours [31,45,46,59].…”