Dipolar optimal control of quantum states

TL;DR

This paper presents a method using quantum optimal control to manipulate dipolar interactions in ultracold atoms, enabling the creation of entangled states with high fidelity, which is promising for quantum technologies.

Contribution

It introduces a novel control scheme leveraging time-dependent magnetic field orientation to generate entangled circulation states in ultracold atom systems.

Findings

Control scheme achieves perfect fidelity in state generation

Fidelity reaches theoretical upper bounds in most cases

Method is applicable across various system sizes

Abstract

Quantum state control is a fundamental tool for quantum technologies. In this work, we propose and analyze the use of quantum optimal control to exploit the dipolar interaction of ultracold atoms on a lattice ring, focusing on the generation of selected states with entangled circulation. This scheme requires time-dependent control over the orientation of the magnetic field, a technique that is feasible in ultracold atom laboratories. The system's evolution is driven by just two independent control functions. We describe the symmetry constraints of this approach and numerically test them using the extended Bose-Hubbard model. We find that the proposed control can engineer entangled current states with perfect fidelity across a wide range of systems, and that in the remaining cases, the theoretical upper bounds for fidelity are reached.