Unifying recent experiments on spin-valley locking in TMDC quantum dots

• URL: http://arxiv.org/abs/2410.21814v1
• Date: Tue, 29 Oct 2024 07:34:06 GMT
• Title: Unifying recent experiments on spin-valley locking in TMDC quantum dots
• Abstract summary: In transition metal dichalcogenides (TMDCs) such spin-valley locking is expected to be particularly strong owing to the significant intrinsic spin-orbit coupling strength. We numerically simulate their ground- and excited-state transport spectroscopy signatures in a unified theoretical framework. Our simulations thus provide a predictive modeling tool for TMDC quantum dots at the few-electron limit.
• Score: 1.027640127328754
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: The spin-valley or Kramers qubit promises significantly enhanced spin-valley lifetimes due to strong coupling of the electrons' spin to their momentum (valley) degrees of freedom. In transition metal dichalcogenides (TMDCs) such spin-valley locking is expected to be particularly strong owing to the significant intrinsic spin-orbit coupling strength. Very recently, a small number of experiments on TMDC quantum dots have put forth evidence for spin-valley locking for the first time at the few-electron limit. Employing quantum transport theory, here we numerically simulate their ground- and excited-state transport spectroscopy signatures in a unified theoretical framework. In doing so, we reveal the operating conditions under which spin-valley locking occurs in TMDC quantum dots, thereby weaving the connection between intrinsic material properties and the experimental data under diverse conditions. Our simulations thus provide a predictive modeling tool for TMDC quantum dots at the few-electron limit allowing us to deduce from experiments the degree of spin-valley locking based on the SOC strength, inter-valley mixing, and the spin and valley $g$-factors. Our theoretical analysis provides an important milestone towards the next challenge of experimentally confirming valley-relaxation times using single-shot projective measurements

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