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arXiv · 0811.3318

Exciton-exciton interaction and biexciton formation in bilayer systems

R. M. Lee·N. D. Drummond·R. J. Needs
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Abstract

We report quantum Monte Carlo calculations of biexciton binding energies in ideal two-dimensional bilayer systems with isotropic electron and hole masses. We have also calculated exciton-exciton interaction potentials, and pair distribution functions for electrons and holes in bound biexcitons. Comparing our data with results obtained in a recent study using a model exciton-exciton potential [C. Schindler and R. Zimmermann, Phys. Rev. B \textbf{78}, 045313 (2008)], we find a somewhat larger range of layer separations at which biexcitons are stable. We find that individual excitons retain their identity in bound biexcitons for large layer separations.

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R. M. Lee, N. D. Drummond, R. J. Needs. 2008-11-20. Exciton-exciton interaction and biexciton formation in bilayer systems. https://doi.org/10.1103/physrevb.79.125308

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