Ultra-sensitive solid-state organic molecular microwave quantum receiver

Bo Zhang; Yuchen Han; Hong-Liang Wu; Hao Wu; Shuo Yang; Mark Oxborrow; Qing Zhao; Yue Fu; Weibin Li; Yeliang Wang; Dezhi Zheng; Jun Zhang

arXiv · 2405.15144

Ultra-sensitive solid-state organic molecular microwave quantum receiver

Bo Zhang·Yuchen Han·Hong-Liang Wu·Hao Wu·Shuo Yang·Mark Oxborrow·Qing Zhao·Yue Fu·Weibin Li·Yeliang Wang·Dezhi Zheng·Jun Zhang

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Abstract

High-accuracy microwave sensing is widely demanded in various fields, ranging from cosmology to microwave quantum technology. Quantum receivers based on inorganic solid-state spin systems are promising candidates for such purpose because of the stability and compatibility, but their best sensitivity is currently limited to a few pT/$\sqrt{\rm{Hz}}$. Here, by utilising an enhanced readout scheme with the state-of-the-art solid-state maser technology, we develop a robust microwave quantum receiver functioned by organic molecular spins at ambient conditions. Owing to the maser amplification, the sensitivity of the receiver achieves 6.14 $\pm$ 0.17 fT/$\sqrt{\rm{Hz}}$ which exceeds three orders of magnitude than that of the inorganic solid-state quantum receivers. The heterodyne detection without additional local oscillators improves bandwidth of the receiver and allows frequency detection. The scheme can be extended to other solid-state spin systems without complicated control pulses and thus enables practical applications such as electron spin resonance spectroscopy, dark matter searches, and astronomical observations.

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Bo Zhang, Yuchen Han, Hong-Liang Wu, Hao Wu, Shuo Yang, Mark Oxborrow, Qing Zhao, Yue Fu, Weibin Li, Yeliang Wang, Dezhi Zheng, Jun Zhang. 2024-05-24. Ultra-sensitive solid-state organic molecular microwave quantum receiver. https://arxiv.org/abs/2405.15144

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