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arXiv · 1610.05080

Non-Hermitian matter wave mixing in Bose Einstein condensates: dissipation induced amplification

S. Wüster·R. El-Ganainy
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Abstract

We investigate the nonlinear scattering dynamics in interacting atomic Bose-Einstein condensates under non-Hermitian dissipative conditions. We show that by carefully engineering a momentum-dependent atomic loss profile one can achieve matter-wave amplification through four wave mixing in a one-dimensional quasi free-space setup - a process that is forbidden in the counterpart Hermitian systems due to energy mismatch. Additionally, we show that similar effects lead to rich nonlinear dynamics in higher dimensions. Finally, we propose a physical realization for selectively tailoring the momentum-dependent atomic dissipation. Our strategy is based on a two step process: (i) exciting atoms to narrow Rydberg- or metastable excited states, and (ii) introducing loss through recoil; all while leaving the bulk condensate intact due to protection by quantum interference.

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S. Wüster, R. El-Ganainy. 2016-10-17. Non-Hermitian matter wave mixing in Bose Einstein condensates: dissipation induced amplification. https://doi.org/10.1103/physreva.96.013605

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