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arXiv · 2207.06611

Suppression of spin bath and low-frequency noise for sub-MHz AC magnetometry based on double-dressed spin qubit in diamond

Kihwan Kim·Yisoo Na·Jungbae Yoon·Dongkwon Lee·Hee Seong Kang·Chul-Ho Lee·Donghun Lee
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Abstract

We experimentally demonstrate a protocol that effectively suppresses the qubit-bath interaction in diamond and enables detection of weak AC signals (below 1 MHz) with enhanced signal-to-noise ratio (SNR) up to SNR = 17. The method is based on AC magnetometry with single- and double-dressed states that are adiabatically transferred from the initial qubit states using concatenated continuous dynamical decoupling. This work paves a way toward sensitive detection of weakly coupled nuclear spins in low-field NMR experiments.

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Kihwan Kim, Yisoo Na, Jungbae Yoon, Dongkwon Lee, Hee Seong Kang, Chul-Ho Lee, Donghun Lee. 2022-07-14. Suppression of spin bath and low-frequency noise for sub-MHz AC magnetometry based on double-dressed spin qubit in diamond. https://doi.org/10.1103/physrevapplied.23.064004

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