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arXiv · 2003.09131

Electron Spin Resonance with up to 20 Spin Sensitivity Measured using a Superconducting Flux Qubit

Rangga P. Budoyo·Kosuke Kakuyanagi·Hiraku Toida·Yuichiro Matsuzaki·Shiro Saito
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Abstract

We report on electron spin resonance spectroscopy measurements using a superconducting flux qubit with a sensing volume of 6 fl. The qubit is read out using a frequency-tunable Josephson bifurcation amplifier, which leads to an inferred measurement sensitivity of about 20 spins in a 1 s measurement. This sensitivity represents an order of magnitude improvement when compared with flux-qubit schemes using a dc-SQUID switching readout. Furthermore, noise spectroscopy reveals that the sensitivity is limited by flicker ($1/f$) flux noise.

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Rangga P. Budoyo, Kosuke Kakuyanagi, Hiraku Toida, Yuichiro Matsuzaki, Shiro Saito. 2020-03-20. Electron Spin Resonance with up to 20 Spin Sensitivity Measured using a Superconducting Flux Qubit. https://doi.org/10.1063/1.5144722

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