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Evolution of excitons via biexcitons to an electron-hole plasma without level crossing between band edge and exciton in a quantum wire

Masahiro Yoshita·Yuhei Hayamizu·Hidefumi Akiyama·Loren N. Pfeiffer·Ken W. West·Kenichi Asano·Tetsuo Ogawa
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Abstract

A recent single quantum wire is of sufficient quality to reveal new details of the photoluminescence (PL) evolution with increasing electron--hole (e--h) pair density. At a pair density of 3.6 $\times$ 10$^{3}$ cm$^{-1}$, the PL is characteristic of biexcitons shifted below the exciton peak by the 2.8-meV biexciton binding. At the pair density of 1.2 $\times$ 10$^{5}$ cm$^{-1}$, the biexciton peak broadens without energy shift to an e--h plasma. At all pair densities up to 30 K, neither the exciton peak nor the one-dimensional (1D) continuum edge shows any shift. In contrast to prevailing theories, the low-energy edge of the plasma PL line never crosses the exciton peak and never makes contact with the 1D e--h continuum.

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Masahiro Yoshita, Yuhei Hayamizu, Hidefumi Akiyama, Loren N. Pfeiffer, Ken W. West, Kenichi Asano, Tetsuo Ogawa. 2005-03-14. Evolution of excitons via biexcitons to an electron-hole plasma without level crossing between band edge and exciton in a quantum wire. https://arxiv.org/abs/cond-mat/0402526

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