3 research outputs found
Raman coupler for a trapped two-component quantum-degenerate Fermi gas
We investigate theoretically the Raman coupling between two internal states
of a trapped low-density quantum-degenerate Fermi gas. In general, the trap
frequencies associated with the two internal states can be different, leading
to the onset of collapses and revivals in the population difference of the two
internal states. This behavior can be changed drastically by two-body
collisions. In particular, we show that under appropriate conditions they can
suppress the dephasing leading to the collapse of the population difference,
and restore almost full Rabi oscillations between the two internal states.
These results are compared and contrasted to those for a quantum-degenerate
bosonic gas.Comment: 7 pages incl. 7 PostScript figures (.eps), LaTeX using RevTeX4,
submitted to Phys. Rev. A, modified versio
Interference scheme to measure light-induced nonlinearities in Bose-Einstein condensates
Light-induced nonlinear terms in the Gross-Pitaevskii equation arise from the
stimulated coherent exchange of photons between two atoms. For atoms in an
optical dipole trap this effect depends on the spatial profile of the trapping
laser beam. Two different laser beams can induce the same trapping potential
but very different nonlinearities. We propose a scheme to measure light-induced
nonlinearities which is based on this observation.Comment: 2 figure
Quantum theory of the far-off-resonance continuous-wave Raman laser: Heisenberg-Langevin approach
We present the quantum theory of the far-off-resonance continuous-wave Raman laser using the Heisenberg-Langevin approach. We show that the simplified quantum Langevin equations for this system are mathematically identical to those of the nondegenerate optical parametric oscillator in the time domain with the following associations: pump pump, Stokes signal, and Raman coherence idler. We derive analytical results for both the steady-state behavior and the time-dependent noise spectra, using standard linearization procedures. In the semiclassical limit, these results match with previous purely semiclassical treatments, which yield excellent agreement with experimental observations. The analytical time-dependent results predict perfect photon statistics conversion from the pump to the Stokes and nonclassical behavior under certain operational conditions