Coherence Properties of a Bose-Einstein Condensate in an Optical Superlattice

TL;DR

This paper investigates how a one-dimensional optical superlattice influences the coherence properties of a Bose-Einstein condensate, revealing reductions in superfluidity, number fluctuations, and interference visibility, with implications for quantum technologies.

Contribution

It provides a detailed analysis of the effects of a secondary lattice on superfluid and Mott-insulator properties, highlighting new insights into coherence control in optical lattices.

Findings

Superfluid fraction decreases with secondary lattice addition.

Number fluctuations are suppressed by the superlattice.

Interference pattern visibility diminishes due to the secondary lattice.

Abstract

We study the effect of a one dimensional optical superlattice on the superfluid fraction, number squeezing, dynamic structure factor and the quasi-momentum distribution of the Mott-insulator. We show that due to the secondary lattice,there is a decrease in the superfluid fraction and the number fluctuation. The dynamic structure factor which can be measured by Bragg spectroscopy is also suppressed due to the addition of the secondary lattice. The visibility of the interference pattern (the quasi-momentum distribution)of the Mott-insulator is found to decrease due to the presence of the secondary lattice. Our results have important implications in atom interferometry and quantum computation in optical lattices.