Nonlinear Resonant Transport of Bose Einstein Condensates

TL;DR

This paper investigates how Bose-Einstein condensates transmit through quantum dots in magnetic waveguides, revealing interaction effects that suppress resonance and proposing a control method to enhance transmission.

Contribution

It introduces a numerical simulation of condensate transport through double barriers, highlighting the impact of interactions and bistability on resonant transport, and suggests a control strategy to improve transmission.

Findings

Resonant transport is suppressed in interaction-induced bistability regimes.

Temporal control of the external potential can enhance transmission.

Enhanced transmission is achievable on realistic time scales.

Abstract

The coherent flow of a Bose-Einstein condensate through a quantum dot in a magnetic waveguide is studied. By the numerical integration of the time-dependent Gross-Pitaevskii equation in presence of a source term, we simulate the propagation process of the condensate through a double barrier potential in the waveguide. We find that resonant transport is suppressed in interaction-induced regimes of bistability, where multiple scattering states exist at the same chemical potential and the same incident current. We demonstrate, however, that a temporal control of the external potential can be used to circumvent this limitation and to obtain enhanced transmission near the resonance on experimentally realistic time scales.