Giant Stokes shifts in AgInS$_2$ nanocrystals with trapped charge carriers

Anvar S. Baimuratov; Irina V. Martynenko; Alexander V. Baranov; Anatoly V. Fedorov; Ivan D. Rukhlenko; Stanislav Yu. Kruchinin

arXiv · 1904.04016

Giant Stokes shifts in AgInS$_2$ nanocrystals with trapped charge carriers

Anvar S. Baimuratov·Irina V. Martynenko·Alexander V. Baranov·Anatoly V. Fedorov·Ivan D. Rukhlenko·Stanislav Yu. Kruchinin

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Abstract

Nanocrystals of AgInS$_2$ demonstrate giant Stokes shifts ~ 1 eV, the nature of which is still not clearly understood. We propose a theoretical model of this phenomenon bringing together several different mechanisms previously considered only separately. We take into account the contribution of electron-electron interaction with the hybrid density functional theory, as well as the renormalization of energy spectrum due to the electron-phonon coupling. Furthermore, we consider the presence of at least one point defect responsible for hole trapping and the formation of a localized polaron state. Our numerical simulations show that photoluminescence due to the recombination of a non-trapped electron and a trapped hole results in the giant Stokes shift in AgInS$_2$ nanocrystal, which is in close agreement with the recent experimental results.

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Anvar S. Baimuratov, Irina V. Martynenko, Alexander V. Baranov, Anatoly V. Fedorov, Ivan D. Rukhlenko, Stanislav Yu. Kruchinin. 2019-04-08. Giant Stokes shifts in AgInS$_2$ nanocrystals with trapped charge carriers. https://arxiv.org/abs/1904.04016

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