Driven Macroscopic Quantum Tunneling of Ultracold Atoms in Engineered Optical Lattices

TL;DR

This paper theoretically investigates how ultracold atoms in engineered optical lattices can exhibit controlled macroscopic quantum tunneling and self-trapping, with potential applications in quantum control.

Contribution

It introduces a method to switch between tunneling and self-trapped states in Bose-Einstein condensates using barrier height pulses, extending understanding of nonlinear quantum dynamics.

Findings

Switching between tunneling and self-trapped states is achievable via barrier height pulses.

The dynamics can be modeled as a particle in a double square well potential.

Results are relevant for both attractive and repulsive atomic interactions.

Abstract

Coherent macroscopic tunneling of a Bose-Einstein condensate between two parts of an optical lattice separated by an energy barrier is theoretically investigated. We show that by a pulsewise change of the barrier height, it is possible to switch between tunneling regime and a self-trapped state of the condensate. This property of the system is explained by effectively reducing the dynamics to the nonlinear problem of a particle moving in a double square well potential. The analysis is made for both attractive and repulsive interatomic forces, and it highlights the experimental relevance of our findings.