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arXiv · 1312.2090

Quantum coherence in momentum space of light-matter condensates

C. Antón·G. Tosi·M. D. Martín·Z. Hatzopoulos·G. Konstantinidis·P. S. Eldridge·P. G. Savvidis·C. Tejedor·L. Viña
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Abstract

We show that the use of momentum-space optical interferometry, which avoids any spatial overlap between two parts of a macroscopic quantum state, presents a unique way to study coherence phenomena in polariton condensates. In this way, we address the longstanding question in quantum mechanics: "\emph{Do two components of a condensate, which have never seen each other, possess a definitive phase?}" [P. W. Anderson, \emph{Basic Notions of Condensed Matter Physics} (Benjamin, 1984)]. A positive answer to this question is experimentally obtained here for light-matter condensates, created under precise symmetry conditions, in semiconductor microcavities taking advantage of the direct relation between the angle of emission and the in-plane momentum of polaritons.

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C. Antón, G. Tosi, M. D. Martín, Z. Hatzopoulos, G. Konstantinidis, P. S. Eldridge, P. G. Savvidis, C. Tejedor, L. Viña. 2013-12-07. Quantum coherence in momentum space of light-matter condensates. https://doi.org/10.1103/physrevb.90.081407

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