Resonant Matter Wave Amplification in Mean Field Theory

Tri Cao Doan; Yuping Huang; Steve F. Wolf; Michael G. Moore

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arXiv · 1112.3325

Resonant Matter Wave Amplification in Mean Field Theory

Tri Cao Doan·Yuping Huang·Steve F. Wolf·Michael G. Moore

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Abstract

We develop a Green's function based mean-field theory for coherent mixing of matter- and light-waves. To demonstrate the utility of this approach, we analyse a co-propagating Raman matter-wave amplifier. We find that for a given laser intensity, a significantly faster amplification process can be achieved employing resonant rather than off-resonance driving. The ratio of the matter-wave gain to atom loss-rate due to spontaneous emission is given by the optical depth of the sample, and is the same both on- and off-resonance. Furthermore, we show that for short-times, the single-mode approximation for the matter-waves gives exact agreement with the full spatial dynamics. For long times, the off-resonant case shows suppressed amplification due to a spatially inhomogenous AC Stark shift associated with laser depletion. This suppression is absent on-resonance, where the AC Stark shift is absent.

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Tri Cao Doan, Yuping Huang, Steve F. Wolf, Michael G. Moore. 2011-12-14. Resonant Matter Wave Amplification in Mean Field Theory. https://arxiv.org/abs/1112.3325

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