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arXiv · 1410.8444

Nonadiabatic multichannel dynamics of a spin-orbit coupled condensate

Abstract

We investigate the nonadiabatic dynamics of a driven spin-orbit-coupled Bose-Einstein condensate in both weak and strong driven force. It is shown that the standard Landau-Zener (LZ) tunneling fails in the regime of weak driven force and/or strong spin-orbital coupling, where the full nonadiabatic dynamics requires a new mechanism through multichannel effects. Beyond the semiclassical approach, our numerical and analytical results show an oscillating power-law decay in the quantum limit, different from the exponential decay in the semiclassical limit of the LZ effect. Furthermore, the condensate density profile is found to be dynamically fragmented by the multichannel effects and enhanced by interaction effects. Our work therefore provides a complete picture to understand the nonadiabatic dynamics of a spin-orbit coupled condensate, including various range of driven force and interaction effects through multichannel interference. The experimental indication of these nonadiabatic dynamics is also discussed.

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Bo Xiong, Jun-hui Zheng, Daw-wei Wang. 2015-06-05. Nonadiabatic multichannel dynamics of a spin-orbit coupled condensate. https://doi.org/10.1103/physreva.91.063602

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