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arXiv · 1312.4647

High-fidelity adiabatic inversion of a $^{31}\mathrm{P}$ electron spin qubit in natural silicon

Arne Laucht·Rachpon Kalra·Juha T. Muhonen·Juan P. Dehollain·Fahd A. Mohiyaddin·Fay Hudson·Jeffrey C. McCallum·David N. Jamieson·Andrew S. Dzurak·Andrea Morello
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Abstract

The main limitation to the high-fidelity quantum control of spins in semiconductors is the presence of strongly fluctuating fields arising from the nuclear spin bath of the host material. We demonstrate here a substantial improvement in single-qubit gate fidelities for an electron spin qubit bound to a $^{31}$P atom in natural silicon, by applying adiabatic inversion instead of narrow-band pulses. We achieve an inversion fidelity of 97%, and we observe signatures in the spin resonance spectra and the spin coherence time that are consistent with the presence of an additional exchange-coupled donor. This work highlights the effectiveness of adiabatic inversion techniques for spin control in fluctuating environments.

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Arne Laucht, Rachpon Kalra, Juha T. Muhonen, Juan P. Dehollain, Fahd A. Mohiyaddin, Fay Hudson, Jeffrey C. McCallum, David N. Jamieson, Andrew S. Dzurak, Andrea Morello. 2013-12-17. High-fidelity adiabatic inversion of a $^{31}\mathrm{P}$ electron spin qubit in natural silicon. https://doi.org/10.1063/1.4867905

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