Near-quantum-limited sensitivity
This detector uses a high-Q superconducting cavity and a near-quantum-limited Josephson parametric amplifier to boost dark photon signals by an order of magnitude, achieving world-leading sensitivity near 26.965 μeV.
Runqi, Kang · Jiao, Man · Yu, Tong · Yang, Liu · Zhong, Youpeng · Cai, Yifu · Zhou, Jingwei · Rong, Xing · Du, Jiangfeng
Physical Review D 2024
Loaded quality factor of superconducting cavity: 6×10⁵
Signal enhancement over copper cavity: more than one order of magnitude
Noise temperature near quantum limit