How the presence of dissipative vortex dynamics affects the superfluid state of a quantum system

• Grant number: 24/13165-2
• Support Opportunities: Regular Research Grants
• Start date: October 01, 2024
• End date: September 30, 2027
• Field of knowledge: Physical Sciences and Mathematics - Physics - Atomic and Molecular Physics
• Principal Investigator: Patrícia Christina Marques Castilho
• Grantee: Patrícia Christina Marques Castilho
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

I will use a new experimental system producing two-dimensional (2D) ultracold quantum gases as a quantum simulator platform [1] to exploit the interplay between coherent superflow and dissipative mechanisms increasing our understanding of how such mechanisms affect the superfluid state of a quantum many-body system. By following the trajectories of deterministically created vortices in a uniform 2D Bose gas with sub-micron resolution and the decay of a superflow in a 2D atomic ring in the presence of pinned/unpinned vortices, we expect to obtain the mutual friction and the diffusion coefficients [2] for a 2D superfluid where the superfluid state is obtained via the Berezinskii- Kosterlitz-Thouless (BKT) phase-transition [3,4]. The increased role of thermal fluctuations in 2D systems, inhibiting the achievement of a fully coherent state with a well-defined phase [5], will surely affect the dynamics of vortices and vortex arrays which will be probed as a function of the temperature of the atomic cloud in the vicinity of the critical point for the BKT transition. In this context, exotic phases of vortex matter are expected to appear in the presence of pinning [6]. Relating our results with the behavior of other more complex quantum systems, e.g. 2D type-II superconducting materials, may provide a better understand of those systems and foment the development of new states of matter and technological devices where dissipation could be strongly suppressed. (AU)