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arXiv · 1404.2057

Relaxation Oscillations in the Formation of a Polariton Condensate

Milena De Giorgi·Dario Ballarini·Paolo Cazzato·George Deligeorgis·Simos I. Tsintzos·Zacharias Hatzopoulos·Pavlos G. Savvidis·Giuseppe Gigli·Fabrice P. Laussy·Daniele Sanvitto
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Abstract

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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Milena De Giorgi, Dario Ballarini, Paolo Cazzato, George Deligeorgis, Simos I. Tsintzos, Zacharias Hatzopoulos, Pavlos G. Savvidis, Giuseppe Gigli, Fabrice P. Laussy, Daniele Sanvitto. 2014-04-08. Relaxation Oscillations in the Formation of a Polariton Condensate. https://doi.org/10.1103/physrevlett.112.113602

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