A Method for the Dynamics of Vortices in a Bose-Einstein Condensate: Analytical Equations of the Trajectories of Phase Singularities

Sergi De María-García, Albert Ferrando, Alberto Conejero, Pedro Fernández De Córdoba, Miguel Ángel García-March. A Method for the Dynamics of Vortices in a Bose-Einstein Condensate: Analytical Equations of the Trajectories of Phase Singularities. Condens. Matter 2023, 8(1), 12. https://doi.org/10.3390/condmat8010012

condmat8010012

Abstract:

We present a method to study the dynamics of a quasi-two dimensional Bose-Einstein condensate which initially contains several vortices at arbitrary locations. The method allows one to find the analytical solution for the dynamics of the Bose-Einstein condensate in a homogeneous medium and in a parabolic trap, for the ideal non-interacting case. Secondly, the method allows one to obtain algebraic equations for the trajectories of the position of phase singularities present in the initial condensate along with time (the vortex lines). With these equations, one can predict quantities of interest, such as the time at which a vortex and an antivortex contained in the initial condensate will merge. For the homogeneous case, this method was introduced in the context of photonics. Here, we adapt it to the context of Bose-Einstein condensates, and we extend it to the trapped case for the first time. Also, we offer numerical simulations in the non-linear case, for repulsive and attractive interactions. We use a numerical split-step simulation of the non-linear Gross-Pitaevskii equation to determine how these trajectories and quantities of interest are changed by the interactions. We illustrate the method with several simple cases of interest, both in the homogeneous and parabolically trapped systems.

Aplicación:

Este artículo representa una aportación metodológica en la construcción de herramientas cuantitativas. En el se propone un esquema analítico–numérico para describir y predecir la dinámica de “eventos críticos” definidos como singularidades (ceros del campo) y obtener sus trayectorias mediante ecuaciones algebraicas, derivando figuras de mérito como tiempos de fusión/aniquilación; además, establece un escenario base analítico (caso lineal) y cuantifica la desviación inducida por no linealidad mediante simulación split-step, lo que constituye un patrón transferible a la futurización de la Huerta para comparar escenarios con distinta complejidad manteniendo trazabilidad. Asimismo, el trabajo conecta con enfoques de IA para la detección automática de estructuras singulares, reforzando el objetivo de Prometeo de integrar modelización interpretable con analítica avanzada para construir indicadores robustos y auditables.