Multi-site gates for state preparation in quantum simulation of the Bose Hubbard Model

TL;DR

This paper introduces multi-site quantum gates that efficiently prepare superfluid states in the Bose-Hubbard model, with exact mappings in specific limits, enabling advanced quantum simulations and measurements.

Contribution

The authors develop a novel sequence of multi-site gates for state preparation in the Bose-Hubbard model, applicable in various interaction regimes and dimensions.

Findings

Exact state mapping in 1D hard core limit

Effective approximation for non-interacting particles in 1D and 2D

Potential use in many-body interferometry

Abstract

We construct a sequence of multi-site gates which transform an easily constructed product state into an approximation to the superfluid ground state of the Bose-Hubbard model. The mapping is exact in the one dimensional hard core limit, and for non-interacting particles in both one and two dimensions. The gate sequence has other applications, such as being used as part of a many-body interferometer which probes the existence of doublons.