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arXiv · 1802.06714

Identification and tunable optical coherent control of transition-metal spins in silicon carbide

Tom Bosma·Gerrit J. J. Lof·Carmem M. Gilardoni·Olger V. Zwier·Freddie Hendriks·Björn Magnusson·Alexandre Ellison·Andreas Gällström·Ivan G. Ivanov·N. T. Son·Remco W. A. Havenith·Caspar H. van der Wal
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Abstract

Color centers in wide-bandgap semiconductors are attractive systems for quantum technologies since they can combine long-coherent electronic spin and bright optical properties. Several suitable centers have been identified, most famously the nitrogen-vacancy defect in diamond. However, integration in communication technology is hindered by the fact that their optical transitions lie outside telecom wavelength bands. Several transition-metal impurities in silicon carbide do emit at and near telecom wavelengths, but knowledge about their spin and optical properties is incomplete. We present all-optical identification and coherent control of molybdenum-impurity spins in silicon carbide with transitions at near-infrared wavelengths. Our results identify spin $S=1/2$ for both the electronic ground and excited state, with highly anisotropic spin properties that we apply for implementing optical control of ground-state spin coherence. Our results show optical lifetimes of $\sim$60 ns and inhomogeneous spin dephasing times of $\sim$0.3 $\mu$s, establishing relevance for quantum spin-photon interfacing.

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Tom Bosma, Gerrit J. J. Lof, Carmem M. Gilardoni, Olger V. Zwier, Freddie Hendriks, Björn Magnusson, Alexandre Ellison, Andreas Gällström, Ivan G. Ivanov, N. T. Son, Remco W. A. Havenith, Caspar H. van der Wal. 2018-02-19. Identification and tunable optical coherent control of transition-metal spins in silicon carbide. https://doi.org/10.1038/s41534-018-0097-8

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