Instability of a two-dimensional Bose–Einstein condensate with Rashba spin–orbit coupling at finite temperature

The condensation of a spin-orbit coupled Bose gas in a uniform gravitational field

“…It shows the condensate fraction is an increasing function of κ for small κ. This is contrary to previous results without a gravitational field that SOC is not in favour of Bose-Einstein condensates [9,12,13]. This results are also different from those with a harmonic trap, where the authors also using a semiclassical method and obtained T c as a decreasing function of spin-orbit coupling strength [22].…”

“…In an isotropic spin-orbit coupled Bose gas, the macroscopic degeneracy of the ground states is of special interest [6][7][8]. It has direct effects on the dispersion relation of excitations, the density of states at low energy, and the stability of Bose-Einstein condensates [9][10][11][12][13][14]. Previously, it was found that there is no stable Bose-Einstein condensate at finite temperature in an ideal Bose gas with an isotropic SOC, due to the divergent density of states in the infrared limit [15].…”

Modulational instability in binary spin-orbit-coupled Bose-Einstein condensates

“…In the combination with the intrinsic matter-wave nonlinearity, the SOC setting offers a platform for the studies of various patterns and collective excitations in the condensates. These studies address the miscibilityimmiscibility transition [8] and the structure and stability of various nonlinear states, including specific structures of the ground state [9], the Bloch spectrum in optical lattices [10], Josephson tunneling [11], fragmentation of condensates [12], tricritical points [13], striped phases [14], supercurrents [15], vortices and vortex lattices [16], solitons, in one- [17], two- [18] and three- [19] dimensional settings, optical and SOC states at finite temperatures [20] etc. Effects of SOC in degenerate Fermi gases were considered too [21].…”

“…The objective of the present work is the analysis of the MI in the effectively one-dimensional SOC system in the framework of the mean-field approach. This is inspired, in particular, by the recent studies of the dynamical instability of supercurrents, as a consequence of the violation of the Galilean invariance by the SOC in one dimension (1D) [15], 2D instability at finite temperatures [20], and phase separation under the action of the SOC [8,33]. The character of the MI, i.e., the dependence of its gain on the perturbation wavenumber, and the structure of the respective perturbation eigenmodes, determine the character of patterns to be generated by the MI.…”