Speaker
Dr
Brandon Anderson
(Joint Quantum Institute)
Description
Isotropic spin-orbit couplings, such as Rashba in two
dimensions, have a continuous symmetry that produces a large
degeneracy in the momentum-space dispersion. This degeneracy
leads to an enhanced density-of-states, producing novel
phases in systems of bosonic atoms. This model is
idealistic, however, in that the symmetry of the lasers will
weakly break the continuous symmetry to a discrete one in
experimental manifestations. This perturbation typically
scales inversely with the optical power, and only at
infinite power will ideal symmetry be restored. In this
talk, we consider the effects of this weak symmetry breaking
in a system of bosons at finite power with synthetic Rashba
coupling. We solve the mean-field equations and find new
phases, such as a stripe phase with a larger symmetry group.
We then consider the experimentally relevant scheme where
the spin-orbit fields are turned on adiabatically from an
initial spin-polarized state. At intermediate power, stripe
phases are found, while at sufficiently high power it
appears that the system quenches to phases similar to that
of the ideal limit. Techniques for optimizing the adiabatic
ramping sequence are discussed.
Primary author
Dr
Brandon Anderson
(Joint Quantum Institute)
