Experimental study of the evolution and relaxation of quantum systems out of equilibrium.

• Grant number: 24/14764-7
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: March 01, 2025
• End date: May 31, 2029
• Field of knowledge: Physical Sciences and Mathematics - Physics - General Physics
• Principal Investigator: Vanderlei Salvador Bagnato
• Grantee: Sarah Sab
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated research grant: 13/07276-1 - CEPOF - Optics and Photonic Research Center, AP.CEPID

Abstract

The dynamics of non-equilibrium closed quantum systems and their route to thermalization are of fundamental interest to diverse fields, from cosmology to particle physics. However, a comprehensive description of disequilibrium phenomena still represents a major challenge: the observation of distinct stages during the turbulence relaxation dynamics in trapped Bose-Einstein condensates. The measurements we had made so far showed that even turbulent systems can demonstrate universal properties. This topic has been extensively investigated in recent years, mainly with more elaborate theoretical descriptions, but few groups have been able to experimentally demonstrate such properties. With experimental evidence, new questions have emerged and new experiments are needed. This PhD project is being proposed precisely so that we can advance our studies on this topic. This project aims to continue studies of the evolution and relaxation of the expanding condensed turbulent cloud, entering the regime of high excitation amplitudes and high moments. The excitation regime in our experiment is done in a temporal zone. In this work we also want to implement excitation in two temporal zones. Depending on the outcome of the observed evolution, one can see how the excitations modify the cloud between the zones, and how the excitations now add up or even interfere destructively. Our understanding of turbulence should be expanded with this study.