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Dissipation Effects in Hybrid Systems
The dissipation effect in a hybrid system is studied in this Letter. The
hybrid system is a compound of a classical magnetic particle and a quantum
single spin. Two cases are considered. In the first case, we investigate the
effect of the dissipative quantum subsystem on the motion of its classical
partner. Whereas in the second case we show how the dynamics of the quantum
single spin are affected by the dissipation of the classical particle.
Extension to general dissipative hybrid systems is discussed.Comment: 4+ pages, 4 figure
Thermodynamic properties of a dipolar Fermi gas
Based on the semi-classical theory, we investigate the thermodynamic
properties of a dipolar Fermi gas. Through a self-consistent procedure, we
numerically obtain the phase space distribution function at finite temperature.
We show that the deformations in both momentum and real space becomes smaller
and smaller as one increases the temperature. For homogeneous case, we also
calculate pressure, entropy, and heat capacity. In particular, at low
temperature limit and in weak interaction regime, we obtain an analytic
expression for the entropy, which agrees qualitatively with our numerical
result. The stability of a trapped gas at finite temperature is also explored
Dynamical properties of a trapped dipolar Fermi gas at finite temperature
We investigate the dynamical properties of a trapped finite-temperature
normal Fermi gas with dipole-dipole interaction. For the free expansion
dynamics, we show that the expanded gas always becomes stretched along the
direction of the dipole moment. In addition, we present the temperature and
interaction dependences of the asymptotical aspect ratio. We further study the
collapse dynamics of the system by suddenly increasing the dipolar interaction
strength. We show that, in contrast to the anisotropic collapse of a dipolar
Bose-Einstein condensate, a dipolar Fermi gas always collapses isotropically
when the system becomes globally unstable. We also explore the interaction and
temperature dependences for the frequencies of the low-lying collective
excitations.Comment: 11 pages, 7 figure
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