PHOENIX -- Paderborn highly optimized and energy efficient solver for two-dimensional nonlinear Schr\"odinger equations with integrated extensions

TL;DR

PHOENIX is a highly optimized, energy-efficient open-source solver for 2D nonlinear Schrödinger equations, capable of modeling complex physical phenomena with significant performance improvements over traditional implementations.

Contribution

The paper introduces PHOENIX, a flexible, high-performance solver for nonlinear Schrödinger equations that achieves substantial speed and energy efficiency gains across various computing architectures.

Findings

Up to 1000x speedup compared to MATLAB implementation

Energy savings of up to 99.8%

Performs close to theoretical performance bounds

Abstract

In this work, we introduce PHOENIX, a highly optimized explicit open-source solver for two-dimensional nonlinear Schr\"odinger equations with extensions. The nonlinear Schr\"odinger equation and its extensions (Gross-Pitaevskii equation) are widely studied to model and analyze complex phenomena in fields such as optics, condensed matter physics, fluid dynamics, and plasma physics. It serves as a powerful tool for understanding nonlinear wave dynamics, soliton formation, and the interplay between nonlinearity, dispersion, and diffraction. By extending the nonlinear Schr\"odinger equation, various physical effects such as non-Hermiticity, spin-orbit interaction, and quantum optical aspects can be incorporated. PHOENIX is designed to accommodate a wide range of applications by a straightforward extendability without the need for user knowledge of computing architectures or performance optimization. The high performance and power efficiency of PHOENIX are demonstrated on a wide range of entry-class to high-end consumer and high-performance computing GPUs and CPUs. Compared to a more conventional MATLAB implementation, a speedup of up to three orders of magnitude and energy savings of up to 99.8% are achieved. The performance is compared to a performance model showing that PHOENIX performs close to the relevant performance bounds in many situations. The possibilities of PHOENIX are demonstrated with a range of practical examples from the realm of nonlinear (quantum) photonics in planar microresonators with active media including exciton-polariton condensates. Examples range from solutions on very large grids, the use of local optimization algorithms, to Monte Carlo ensemble evolutions with quantum noise enabling the tomography of the system's quantum state.