SAMOP 2023 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
Q: Fachverband Quantenoptik und Photonik
Q 26: Quantum Gases: Bosons III
Q 26.3: Talk
Wednesday, March 8, 2023, 11:30–11:45, E214
Out of equilibrium dynamical properties of Bose-Einstein condensates in ramped up weak disorder — •Milan Radonjić1,2, Rodrigo P. A. Lima3,4, and Axel Pelster4 — 1I. Institute of Theoretical Physics, University of Hamburg, Germany — 2Institute of Physics Belgrade, University of Belgrade, Serbia — 3GISC and GFTC, Instituto de Física, Universidade Federal de Alagoas, Maceió AL, Brazil — 4Physics Department and Research Center OPTIMAS, Technical University of Kaiserslautern, Germany
We investigate theoretically how the superfluid and the condensate deformation of a weakly interacting ultracold Bose gas evolve during the ramping up of an external weak disorder potential. Both resulting deformations turn out to consist of two distinct contributions, namely a reversible equilibrium one [1,2], as well as a non-equilibrium dynamical one, whose magnitude depends on the details of the ramping protocol [3]. For the specific case of the exponential ramping up protocol, we are able to derive analytic time-dependent expressions for the aforementioned quantities. After sufficiently long time, the steady state emerges that is generically out of equilibrium. We make the first step in examining its properties by studying the relaxation dynamics into it. Also, we investigate the two-time correlation function and elucidate its relation to the equilibrium and the dynamical part of the condensate deformation. [1] K. Huang and H.-F. Meng, Phys. Rev. Lett. 69, 644 (1992). [2] B. Nagler, M. Radonjić, S. Barbosa, J. Koch, A. Pelster, and A. Widera, New J. Phys. 22, 033021 (2020). [3] M. Radonjić and A. Pelster, SciPost Phys. 10, 008 (2021)