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Exciton-relaxation dynamics in lead halides

Masanobu Iwanaga·Tetsusuke Hayashi
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Abstract

We survey recent comprehensive studies of exciton relaxation in the crystals of lead halides. The luminescence and electron-spin-resonance studies have revealed that excitons in lead bromide spontaneously dissociate and both electrons and holes get self-trapped individually. Similar relaxation has been also clarified in lead chloride. The electron-hole separation is ascribed to repulsive correlation via acoustic phonons. Besides, on the basis of the temperature profiles of self-trapped states, we discuss the origin of luminescence components which are mainly induced under one-photon excitation into the exciton band in lead fluoride, lead chloride, and lead bromide.

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Masanobu Iwanaga, Tetsusuke Hayashi. 2002-08-16. Exciton-relaxation dynamics in lead halides. https://doi.org/10.1016/s0022-2313(02)00619-1

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