Exact kinetic propagators for coherent state complex Langevin simulations

TL;DR

This paper presents an improved complex Langevin simulation algorithm for bosonic coherent state path integrals, using a Strang splitting method that enhances stability and efficiency without significant computational overhead.

Contribution

The authors develop a higher-order propagator approach with guaranteed linear stability, outperforming traditional methods in bosonic systems with complex interactions.

Findings

Enhanced stability in simulations independent of discretization

Improved efficiency in single- and two-component bosonic systems

Successful benchmarking demonstrating performance gains

Abstract

We introduce and benchmark an improved algorithm for complex Langevin simulations of bosonic coherent state path integrals. Our approach utilizes a Strang splitting of the imaginary-time propagator rather than the conventional linear-order Taylor expansion, allowing us to construct an action that incorporates higher-order terms at negligible computational cost. The resulting algorithm enjoys guaranteed linear stability independent of the imaginary-time discretization, enabling more resource-efficient simulations. We demonstrate this improved performance for single-species bosons and for two-component bosons with Rashba spin-orbit coupling.