QEngine: An open-source C++ Library for Quantum Optimal Control of Ultracold Atoms

TL;DR

QEngine is an open-source C++ library designed for simulating and optimizing control of ultracold quantum systems like Bose-Einstein condensates and many-body systems, integrating advanced algorithms such as the GROUP method.

Contribution

This work introduces the first version of QEngine, a library that combines simulation and optimal control algorithms for ultracold quantum systems in a user-friendly and high-performance framework.

Findings

Supports simulation of Bose-Einstein condensates and Bose-Hubbard models

Includes advanced optimal control algorithms like the GROUP method

Provides practical examples for system preparation and control

Abstract

We present the first version of the QEngine, an open-source C++ library for simulating and controlling ultracold quantum systems using optimal control theory (OCT). The most notable systems presented here are Bose-Einstein condensates, many-body systems described by Bose-Hubbard type models, and two interacting particles. These systems can all be realized experimentally using ultracold atoms in various trapping geometries including optical lattices. In addition we provide a number of optimal control algorithms including the recently introduced GROUP method. The QEngine library has a strong focus on accessibility and performance. We provide several examples of how to prepare simulations of the physical systems and apply optimal control.