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arXiv · 2312.03138

Direct biexciton generation in Si nanocrystal by a single photon

Sergey Fomichev·Vladimir Burdov
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Abstract

It has been shown theoretically that strong quantum confinement regime in Si nanocrystals promotes the highly efficient simultaneous excitation of two electron-hole pairs (biexciton) by a single photon. The rate (inverse lifetime) of biexciton generation has been calculated analytically as function of the nanocrystal radius. In contrast to the case of a nanocrystal formed of direct-band-gap semiconductor, the size-dependence of the rate in Si nanocrystal turns out to be sharp enough. At radii approaching a nanometer, the lifetime of biexciton generation falls into the nanosecond range.

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Sergey Fomichev, Vladimir Burdov. 2023-12-05. Direct biexciton generation in Si nanocrystal by a single photon. https://arxiv.org/abs/2312.03138

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