Hamiltonian of a Spin-1 Bose-Einstein Condensate

Shi-Jie Yang, Zhihai Zhang

Michael Chapman

I will discuss our experimental results investigating strongly interacting spin ensembles realized in spin-1 atomic Bose-Einstein condensates. These condensates feature a well-characterized tunable Hamiltonian with a quantum phase transition that provide a unique combination of tools to explore quantum spin dynamics including generation of spin-squeezed states.

Duger Ulam-Orgikh, Purevdorj Munkhbaatar

In this Paper, we have dealt with two-axis twisting Hamiltonian for spin squeezing, which is experimentally implementable in Bose-Einstein Condensate, and have found an exact solution by two alternative methods. Many other important nonlinear Hamiltonians could also be solved exactly in a similar way.

Xiaoqiang Xu, Jung Hoon Han

Hydrodynamic theory of the spinor BEC condensate with Rashba spin-orbit coupling is presented. A close mathematical analogy of the Rashba-Bose-Einstein condensate model to the recently developed theory of chiral magnetism is found. Hydrodynamic equations for mass density, superfluid velocity, and the local magnetization are derived. The mass current is shown to contain an extra term proportional to the magnetization direction, as a result of the Rashba coupling. Elementary excitations around the two known ground states of the Rashba-Bose-Einstein condensate Hamiltonian, the plane-wave, and the stripe states, are worked out in the hydrodynamic framework, highlighting the cross coupling of spin and superflow velocity excitations due to the Rashba term.

Benjamin P. Stein