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arXiv · 1607.01086

Characterizing Si:P quantum dot qubits with spin resonance techniques

Yu Wang·Chin-Yi Chen·Gerhard Klimeck·Michelle Y. Simmons·Rajib Rahman
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Abstract

Quantum dots patterned by atomically precise placement of phosphorus donors in single crystal silicon have long spin lifetimes, advantages in addressability, large exchange tunability, and are readily available few-electron systems. To be utilized as quantum bits, it is important to non-invasively characterise these donor quantum dots post fabrication and extract the number of bound electron and nuclear spins as well as their locations. Here, we propose a metrology technique based on electron spin resonance (ESR) measurements with the on-chip circuitry already needed for qubit manipulation to obtain atomic scale information about donor quantum dots and their spin configurations. Using atomistic tight-binding technique and Hartree self-consistent field approximation, we show that the ESR transition frequencies are directly related to the number of donors, electrons, and their locations through the electron-nuclear hyperfine interaction.

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Yu Wang, Chin-Yi Chen, Gerhard Klimeck, Michelle Y. Simmons, Rajib Rahman. 2016-07-05. Characterizing Si:P quantum dot qubits with spin resonance techniques. https://arxiv.org/abs/1607.01086

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