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Relaxation Oscillations in the Formation of a Polariton Condensate

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 نشر من قبل Milena De Giorgi
 تاريخ النشر 2014
  مجال البحث فيزياء
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We report observation of oscillations in the dynamics of a microcavity polariton condensate formed under pulsed non resonant excitation. While oscillations in a condensate have always been attributed to Josephson mechanisms due to a chemical potential unbalance, here we show that under some localisation conditions of the condensate, they may arise from relaxation oscillations, a pervasive classical dynamics that repeatedly provokes the sudden decay of a reservoir, shutting off relaxation as the reservoir is replenished. Using non-resonant excitation, it is thus possible to obtain condensate injection pulses with a record frequency of 0:1 THz.



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