Dominici L, Petrov M, Matuszewski M, Ballarini D, De Giorgi M, Colas D, Cancellieri E, Silva Fernández B, Bramati A, Gigli G, Kavokin A, Laussy F, Sanvitto D
CNR NANOTEC-Istituto di Nanotecnologia, Via Monteroni, 73100 Lecce, Italy.
Spin Optics Laboratory, Saint Petersburg State University, 198504 St Petersburg, Russia.
Nat Commun. 2015 Dec 4;6:8993. doi: 10.1038/ncomms9993.
Microcavity polaritons are two-dimensional bosonic fluids with strong nonlinearities, composed of coupled photonic and electronic excitations. In their condensed form, they display quantum hydrodynamic features similar to atomic Bose-Einstein condensates, such as long-range coherence, superfluidity and quantized vorticity. Here we report the unique phenomenology that is observed when a pulse of light impacts the polariton vacuum: the fluid which is suddenly created does not splash but instead coheres into a very bright spot. The real-space collapse into a sharp peak is at odd with the repulsive interactions of polaritons and their positive mass, suggesting that an unconventional mechanism is at play. Our modelling devises a possible explanation in the self-trapping due to a local heating of the crystal lattice, that can be described as a collective polaron formed by a polariton condensate. These observations hint at the polariton fluid dynamics in conditions of extreme intensities and ultrafast times.
微腔极化激元是由耦合的光子和电子激发组成的具有强非线性的二维玻色流体。在其凝聚态下，它们表现出与原子玻色 - 爱因斯坦凝聚体相似的量子流体动力学特征，如长程相干性、超流性和量子化涡度。在此，我们报告了当光脉冲撞击极化激元真空时所观察到的独特现象：突然产生的流体不会飞溅，而是凝聚成一个非常亮的点。在实空间中坍缩成一个尖锐的峰与极化激元的排斥相互作用及其正质量相悖，这表明一种非常规机制在起作用。我们的模型提出了一种可能的解释，即由于晶格的局部加热导致的自陷，这可以描述为由极化激元凝聚体形成的集体极化子。这些观察结果暗示了在极端强度和超快时间条件下的极化激元流体动力学。
