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arXiv · 1909.08778

Coherent control and high-fidelity readout of chromium ions in commercial silicon carbide

Berk Diler·Samuel J. Whiteley·Christopher P. Anderson·Gary Wolfowicz·Marie E. Wesson·Edward S. Bielejec·F. Joseph Heremans·David Awschalom
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Abstract

Transition metal ions provide a rich set of optically active defect spins in wide bandgap semiconductors. Chromium (Cr4+) in silicon-carbide (SiC) produces a spin-1 ground state with a narrow, spectrally isolated, spin-selective, near-telecom optical interface. However, previous studies were hindered by material quality resulting in limited coherent control. In this work, we implant Cr into commercial 4H-SiC and show optimal defect activation after annealing above 1600 C. We measure an ensemble optical hole linewidth of 31 MHz, an order of magnitude improvement compared to as-grown samples. An in-depth exploration of optical and spin dynamics reveals efficient spin polarization, coherent control, and readout with high fidelity (79%). We report T1 times greater than 1 second at cryogenic temperatures (15 K) with a T2* = 317 nanoseconds and a T2 = 81 microseconds, where spin dephasing times are currently limited by spin-spin interactions within the defect ensemble. Our results demonstrate the potential of Cr4+ in SiC as an extrinsic, optically active spin qubit.

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Berk Diler, Samuel J. Whiteley, Christopher P. Anderson, Gary Wolfowicz, Marie E. Wesson, Edward S. Bielejec, F. Joseph Heremans, David Awschalom. 2019-09-19. Coherent control and high-fidelity readout of chromium ions in commercial silicon carbide. https://arxiv.org/abs/1909.08778

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