Journal of Physics B: Atomic, Molecular and Optical Physics
Doi
Abstract
We study theoretically a driven dissipative one-dimensional XXZ spin−1/2
chain with dipole coupling and a tunable strength of the Ising and XY
interaction. Within a mean-field approximation, we find a rich phase diagram
with uniform, spin density wave, antiferromagnetic and oscillatory phases, as
well as regions of phase bistability. We study the phase diagram of small
quantum systems using exact diagonalisation, and compare the results to the
mean-field theory. We find that while expectation values only capture the
uniform phases of the mean-field theory, fluctuations about these expectation
values give signatures of spatially non-uniform phases and bistabilities. We
find these signatures for all ratios of the Ising to XY interaction, showing
that they appear to be general features of spin−1/2 system