Silicon Vacancies in Silicon Carbide for Quantum Applications

Silicon Vacancies in Silicon Carbide for Quantum Applications
Matthias Widmann
13rd Institute of Physics & IQST & SCOPE, Stuttgart, Germany
E-mail: m.widmann@physik.uni-stuttgart.de

Atomic scale defects in solids have attracted a great amount of interest over the last decades, because their spins show a promising potential as stationary qubits in quantum information processing and sensitive quantum sensors. Leading systems are colour centres in diamond, e.g. the negatively charged nitrogen-vacancy centre, and impurities in silicon. However, the large band gap and exceptional hardness of diamond hinder the development of quantum devices. This problem can be overcome by switching to another host material, namely silicon carbide (SiC). SiC can combine the advantages of both diamond and silicon, offering single spins accessible optically at room temperature embedded in a CMOS compatible material. In this presentation, we introduce the silicon vacancy spin qubits [1] and their application for magnetometry [2], and recent efforts towards understanding of the charge state and electrical manipulation of colour centres in SiC quantum devices [3,4]. We also show that the silicon vacancy combines a high Debye-Waller factor of 50% with a relative spin contrast of nearly 100% [5], and discuss its potential use for an efficient spin-to-photon interface [6].

References

[1] M. Widmann, et al., Nat Mater. 14,164 (2015)
[2] M. Niethammer, et al., Phys. Rev. Applied 6, 034001 (2015)
[3] M. Widmann, et al., Appl. Phys. Lett. 112, 231103 (2018).
[4] M. Widmann, et al., to be submitted
[5] R. Nagy, et al., Phys. Rev. Appl. 9, 34022 (2018).
[6] R. Nagy, et al., arXiv:1810.10296 (2018)