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Spontaneous Polarisation Build up in a Room Temperature Polariton Laser

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 نشر من قبل Jeremy Baumberg
 تاريخ النشر 2008
  مجال البحث فيزياء
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We observe the build up of strong (~50%) spontaneous vector polarisation in emission from a GaN-based polariton laser excited by short optical pulses at room temperature. The Stokes vector of emitted light changes its orientation randomly from one excitation pulse to another, so that the time-integrated polarisation remains zero. This behaviour is completely different to any previous laser. We interpret this observation in terms of the spontaneous symmetry breaking in a Bose-Einstein condensate of exciton-polaritons.

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