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arXiv · 1004.3475

Bismuth in silicon qubits: the role of EPR cancellation resonances

M. H. Mohammady·G. W. Morley·T. S. Monteiro
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Abstract

We investigate theoretically and experimentally the electron paramagnetic resonance (EPR) spectra of bismuth doped silicon (Si:Bi) at intermediate magnetic fields, $B \approx 0.05 -0.6$ T. We identify a previously unexplored EPR regime of "cancellation-resonances"- where part of the hyperfine coupling is resonant with the external field-induced splitting. We show this regime has interesting and experimentally accessible consequences for spectroscopy and quantum information applications. These include reduction of decoherence, fast manipulation of the coupled nuclear-electron qubit system and line narrowing in the multi-qubit case. We test our theoretical analysis by comparing with experimental X-band (9.7 GHz) EPR spectra obtained in the intermediate field regime.

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M. H. Mohammady, G. W. Morley, T. S. Monteiro. 2010-08-25. Bismuth in silicon qubits: the role of EPR cancellation resonances. https://doi.org/10.1103/physrevlett.105.067602

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