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arXiv · 1911.01123

Three-dimensional electron-hole superfluidity in a superlattice close to room temperature

M. Van der Donck·S. Conti·A. Perali·A. R. Hamilton·B. Partoens·F. M. Peeters·D. Neilson
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Abstract

Although there is strong theoretical and experimental evidence for electron-hole superfluidity in separated sheets of electrons and holes at low $T$, extending superfluidity to high $T$ is limited by strong 2D fluctuations and Kosterlitz-Thouless effects. We show this limitation can be overcome using a superlattice of alternating electron- and hole-doped semiconductor monolayers. The superfluid transition in a 3D superlattice is not topological, and for strong electron-hole pair coupling, the transition temperature $T_c$ can be at room temperature. As a quantitative illustration, we show $T_c$ can reach $270$ K for a superfluid in a realistic superlattice of transition metal dichalcogenide monolayers.

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M. Van der Donck, S. Conti, A. Perali, A. R. Hamilton, B. Partoens, F. M. Peeters, D. Neilson. 2019-11-04. Three-dimensional electron-hole superfluidity in a superlattice close to room temperature. https://doi.org/10.1103/physrevb.102.060503

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