2011/11/30 by G. J. Schinner, J. Repp, Schinner, G. J. +19
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #FOS: Physical sciences #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum and electron transport phenomena #Semiconductor Quantum Structures and Devices #cond-mat.mes-hall
paper · pdf · doi:10.48550/arxiv.1111.7175
openalex publication_date 2011/11/30 · arxiv created 2012/04/14 · arxiv updated 2012/04/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study the photoluminescence (PL) of a two-dimensional liquid of oriented dipolar excitons in InxGa1-xAs coupled double quantum wells confined to a microtrap. Generating excitons outside the trap and transferring them at lattice temperatures down to T = 240 mK into the trap we create cold quasi-equilibrium bosonic ensembles of some 1000 excitons with thermal de Broglie wavelengths exceeding the excitonic separation. With decreasing temperature and increasing density n <= 5*1010 cm-2 we find an increasingly asymmetric PL lineshape with a sharpening blue edge and a broad red tail which we interpret to reflect correlated behavior mediated by dipolar interactions. From the PL intensity I(E) below the PL maximum at E0 we extract at T < 5 K a distinct power law I(E) ∼ (E0-E)-|α| with -|α|∼ -0.8 in the range E0-E of 1.5-4 meV, comparable to the dipolar interaction energy.