Defects as qubits in 3C- and 4H-SiC
Date
2015-07-20
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Publisher
American Physical Society
Abstract
We employ hybrid density functional calculations to search for defects in different polytypes of SiC that
may serve as qubits for quantum computing. We explore the divacancy in 4H- and 3C-SiC, consisting of a
carbon vacancy adjacent to a silicon vacancy, and the nitrogen-vacancy (NV) center in 3C-SiC, in which the
substitutional NC sits next to a Si vacancy (NC-VSi). The calculated excitation and emission energies of the
divacancy in 4H-SiC are in excellent agreement with experimental data, and aid in identifying the four unique
configurations of the divacancy with the four distinct zero-phonon lines observed experimentally. For 3C-SiC,
we identify the paramagnetic defect that was recently shown to maintain a coherent quantum state up to room
temperature as the spin-1 neutral divacancy. Finally, we show that the (NC-VSi)− center in 3C-SiC is highly
promising for quantum information science, and we provide guidance for identifying this defect.
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Citation
Gordon, L., A. Janotti, and C. G. Van de Walle. "Defects as qubits in 3 C− and 4 H− SiC." Physical Review B 92.4 (2015): 045208.