Atomic quantum dots coupled to BEC reservoirs

TL;DR

This paper investigates atomic quantum dots coupled to Bose-Einstein condensate reservoirs, demonstrating tunable dissipation and phase transitions, and providing a platform to measure Luttinger parameters in 1D cold atom systems.

Contribution

It introduces a method to control the coupling of atomic quantum dots to superfluid reservoirs, enabling the study of dissipative phase transitions and measurement of Luttinger parameters.

Findings

Tunable coupling of quantum dots to phonon baths via quantum interference.

Observation of a dissipative phase transition in a spin-Boson model.

Direct measurement of atomic Luttinger parameters in 1D systems.

Abstract

We study the dynamics of an atomic quantum dot, i.e. a single atom in a tight optical trap which is coupled to a superfluid reservoir via laser transitions. Quantum interference between the collisional interactions and the laser induced coupling to the phase fluctuations of the condensate results in a tunable coupling of the dot to a dissipative phonon bath, allowing an essentially complete decoupling from the environment. Quantum dots embedded in a 1D Luttinger liquid of cold bosonic atoms realize a spin-Boson model with ohmic coupling, which exhibits a dissipative phase transition and allows to directly measure atomic Luttinger parameters.