Mainz 2017 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

Q: Fachverband Quantenoptik und Photonik

Q 31: Poster: Quantum Optics and Photonics I

Q 31.7: Poster

Tuesday, March 7, 2017, 17:00–19:00, P OG1+2

Non-equilibrium dynamics of an F=1 spinor Bose-Einstein condensate — •Kevin Geier¹, Christian-Marcel Schmied¹, Sebastian Erne^2,3, and Thomas Gasenzer¹ — ¹Kirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 227, 69120 Heidelberg, Germany — ²Institut für Theoretische Physik, Ruprecht-Karls-Universität Heidelberg, Philosophenweg 16, 69120 Heidelberg, Germany — ³Vienna Center for Quantum Science and Technology, Atominstitut, TU Wien, Stadionallee 2, 1020 Wien, Austria

We study the dynamics of an F=1 spinor Bose-Einstein condensate in one spatial dimension out of equilibrium by means of semi-classical simulations. Our main focus lies on sudden quenches within the paramagnetic phase, where the system is quenched near the critical point of a phase transition by varying an external magnetic field. The time evolution of the resulting non-equilibrium state including quantum effects is studied within the framework of the truncated Wigner approximation. To this end, the coupled Gross-Pitaevskii equations for the fundamental fields are solved numerically using higher-order time-splitting Fourier pseudospectral methods. We observe the formation of soliton-like excitations and study their link to the build-up of correlations in the system. By continuously tuning the interaction away from an integrable point of the system, we further investigate the effects of non-integrability on the observed dynamics. Our results are put into relation with the concept of non-thermal fixed points and critical phenomena.