Research on Intrinsic Expansion Coefficients in Rydberg Atomic Heterodyne Receiving Link

Rydberg atom can respond to weak microwave electric field signal in real-time by using its electromagnetically induced transparency effect to realize down conversion of space microwave electric field signal, which can be used as a superheterodyne receiver. The Rydberg atom superheterodyne receiver is a new receiving system composed of Rydberg atoms, photodetectors, and electronic information processing modules. Presently, domestic and foreign scholars have conducted in-depth research on the physical response mechanism of Rydberg atomic superheterodyne receiving technology. However, no complete receiving link analysis model has been established, which is not conducive to optimizing its system performance. Based on the physical mechanism of the Rydberg atom responding to the microwave electric field, this paper introduces the concept of intrinsic expansion coefficient, establishes and experimentally verifies the receiving link model of the Rydberg atom superheterodyne receiver, and briefly discusses the influence of the intrinsic expansion coefficient on the system sensitivity and response characteristics, which provides theoretical guidance for the optimization of the performance of the Rydberg atom superheterodyne receiving system. Last, the Rydberg atomic and the electronic receiving links' sensitivity performance is discussed and compared.