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arXiv · 2007.14399

Dynamic modulation of phonon-assisted transitions in quantum defects in monolayer transition-metal dichalcogenide semiconductors

Chitraleema Chakraborty·Christopher J. Ciccarino·Prineha Narang
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Abstract

Quantum localization via atomic point defects in semiconductors is of significant fundamental and technological importance. Quantum defects in monolayer transition-metal dichalcogenide semiconductors have been proposed as stable and scalable optically-addressable spin qubits. Yet, the impact of strong spin-orbit coupling on their dynamical response, for example under optical excitation, has remained elusive. In this context, we study the effect of spin-orbit coupling on the electron-phonon interaction in a single chalcogen vacancy defect in monolayer transition metal dichalcogenides, molybdenum disulfide (MoS$_2$) and tungsten disulfide (WS$_2$). From ab initio electronic structure theory calculations, we find that spin-orbit interactions tune the magnitude of the electron-phonon coupling in both optical and charge-state transitions of the defect, modulating their respective efficiencies. This observation opens up a promising scheme of dynamically modulating material properties to tune the local behavior of a quantum defect.

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Chitraleema Chakraborty, Christopher J. Ciccarino, Prineha Narang. 2020-07-28. Dynamic modulation of phonon-assisted transitions in quantum defects in monolayer transition-metal dichalcogenide semiconductors. https://arxiv.org/abs/2007.14399

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