Experimental Study Of Quantum Gas With Spin-Orbit Coupling

This thesis is based on Bose-Einstein condensate investigating unconven-tional behavior of spin-orbit (SO) coupled quantum gas produced by Raman coupling technique.In this thesis, recently experimental progress of quantum degenerate gas and basic theory of Bose-Einstein condensation are introduced. Moreover, we provide the original, theory and some recent proposals of artificial gauge potential and spin-orbit coupling.For the setup of Bose-Einstein condensate, firstly we introduce the ultra-high vacuum system, whose vacuum degree is about10-11mbar; secondly, we describe the Laser cooling system, including two dimension and three dimension magneto-optical trap (MOT); thirdly, we introduce optical dipole trap, which is all-optical formation of Bose-Einstein condensate by evaporate cooling; lastly, we provide the image system to diagnose the atom cloud.We investigate the unique macroscopic quantum behavior of spin-orbit cou-pled Bose gas produced by Raman coupling technique. We describe the collective dipole oscillations of a spin-orbit coupled Bose-Einstein condensate in harmonic trap, use the oscillation amplitude to deduce the spin polarization susceptibility χ and discover quantum phase transition by χ→∞; we also study the stability of excited dressed states with spin-orbit coupling, demonstrate that there are two SO coupling induced decay mechanisms, i.e. trapping frequency and interatomic interaction; final, we show the phase diagram of Bose gas with SO coupling at finite temperature and first experimental demonstrate the property of SO coupled Bose gas.