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arXiv · 1912.04612

Spin-relaxation times exceeding seconds for color centers with strong spin-orbit coupling in SiC

Carmem M. Gilardoni·Tom Bosma·Danny van Hien·Freddie Hendriks·Björn Magnusson·Alexandre Ellison·Ivan G. Ivanov·N. T. Son·Caspar H. van der Wal
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Abstract

Spin-active color centers in solids show good performance for quantum technologies. Several transition-metal defects in SiC offer compatibility with telecom and semiconductor industries. However, whether their strong spin-orbit coupling degrades their spin lifetimes is not clear. We show that a combination of a crystal-field with axial symmetry and spin-orbit coupling leads to a suppression of spin-lattice and spin-spin interactions, resulting in remarkably slow spin relaxation. Our optical measurements on an ensemble of Mo impurities in SiC show a spin lifetime $T_1$ of $2,4$ s at $2$ K.

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Carmem M. Gilardoni, Tom Bosma, Danny van Hien, Freddie Hendriks, Björn Magnusson, Alexandre Ellison, Ivan G. Ivanov, N. T. Son, Caspar H. van der Wal. 2019-12-10. Spin-relaxation times exceeding seconds for color centers with strong spin-orbit coupling in SiC. https://doi.org/10.1088/1367-2630%2Fabbf23

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