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arXiv · 2011.12006

Quantum confined Rydberg excitons in Cu$_2$O nanoparticles

Konstantinos Orfanakis·Sai Kiran Rajendran·Hamid Ohadi·Sylwia Zielińska-Raczyńska·Gerard Czajkowski·Karol Karpiński·David Ziemkiewicz
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Abstract

The quantum confinement of Rydberg excitons is an important step towards exploiting their large nonlinearities for quantum applications. We observe Rydberg excitons in natural nanoparticles of Cu$_2$O. We resolve up to the principal quantum number $n=12$ in a bulk Cu$_2$O crystal and up to $n=6$ in nanoparticles extracted from the same crystal. The exciton transitions in nanoparticles are broadened and their oscillator strengths decrease as $\propto n^{-4}$ compared to those in the bulk (decreasing as $\propto n^{-3}$). We explain our results by including the effect of quantum confinement of exciton states in the nanoparticles. Our results provide an understanding of the physics of Cu$_2$O Rydberg excitons in confined dimensions.

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Konstantinos Orfanakis, Sai Kiran Rajendran, Hamid Ohadi, Sylwia Zielińska-Raczyńska, Gerard Czajkowski, Karol Karpiński, David Ziemkiewicz. 2020-11-24. Quantum confined Rydberg excitons in Cu$_2$O nanoparticles. https://doi.org/10.1103/physrevb.103.245426

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