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arXiv · 1411.4519

Atomic selfordering in a ring cavity with counterpropagating pump

S. Ostermann·T. Grießer·H. Ritsch
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Abstract

The collective dynamics of mobile scatterers and light in optical resonators generates complex behaviour. For strong transverse illumination a phase transition from homogeneous to crystalline particle order appears. In contrast, a gas inside a single-side pumped ring cavity exhibits an instability towards bunching and collective acceleration called collective atomic recoil lasing (CARL). We demonstrate that by driving two orthogonally polarized counter propagating modes of a ring resonator one realises both cases within one system. The corresponding phase diagram depending on the two pump intensities exhibits regions in which either a generalized form of self-ordering towards a travelling density wave with constant centre of mass velocity or a CARL instability is formed. Controlling the cavity driving then allows to accelerate or slow down and trap a sufficiently dense beam of linearly polarizable particles.

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S. Ostermann, T. Grießer, H. Ritsch. 2014-11-17. Atomic selfordering in a ring cavity with counterpropagating pump. https://doi.org/10.1209/0295-5075%2F109%2F43001

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