Excitonic Condensation in an Asymmetric Electron-Hole Biwire

Gautam Shah; Vinod Ashokan; N. D. Drummond; K. N. Pathak

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arXiv · 2606.17086

Excitonic Condensation in an Asymmetric Electron-Hole Biwire

Gautam Shah·Vinod Ashokan·N. D. Drummond·K. N. Pathak

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Abstract

We study a mass-asymmetric one-dimensional electron-hole biwire system at zero temperature using the diffusion quantum Monte Carlo method. Pair correlation functions and condensate fraction are obtained over a wide range of carrier densities $r_{\rm s}$ and interwire separations $d$, allowing us to construct the phase diagram. We identify regimes corresponding to a two-component electron-hole plasma, an excitonic fluid with quasicondensation, and a Wigner-correlated phase at various densities. Owing to reduced dimensionality, strong electron-hole correlations favor excitonic quasicondensation even in the high-density limit, persisting down to $r_{\rm s} = 0.3$ a.u. These results provide a microscopic characterization of correlation-driven phases in electron-hole systems in one dimension.

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Gautam Shah, Vinod Ashokan, N. D. Drummond, K. N. Pathak. 2026-06-12. Excitonic Condensation in an Asymmetric Electron-Hole Biwire. https://arxiv.org/abs/2606.17086

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