Spin-defect characteristics of single sulfur vacancies in monolayer MoS2
Alexander Hötger, Tomer Amit, Julian Klein, Katja Barthelmi, Thomas Pelini, Alex Delhomme, Sergio I. Rey, M. Potemski, C. Faugeras, Galit Cohen, Daniel Hernangómez‐Pérez, Takashi Taniguchi, Kenji Watanabe, Christoph Kastl, Jonathan J. Finley, Sivan Refaely‐Abramson, Alexander W. Holleitner, Andreas V. Stier
Abstract
Abstract Single spin-defects in 2D transition-metal dichalcogenides are natural spin-photon interfaces for quantum applications. Here we report high-field magneto-photoluminescence spectroscopy from three emission lines (Q1, Q2, and Q*) of He-ion induced sulfur vacancies in monolayer MoS 2 . Analysis of the asymmetric PL lineshapes in combination with the diamagnetic shift of Q1 and Q2 yields a consistent picture of localized emitters with a wave function extent of ~3.5 nm. The distinct valley-Zeeman splitting in out-of-plane B -fields and the brightening of dark states through in-plane B -fields necessitates spin-valley selectivity of the defect states and lifted spin-degeneracy at zero field. Comparing our results to ab initio calculations identifies the nature of Q1 and Q2 and suggests that Q* is the emission from a chemically functionalized defect. Analysis of the optical degree of circular polarization reveals that the Fermi level is a parameter that enables the tunability of the emitter. These results show that defects in 2D semiconductors may be utilized for quantum technologies.