We propose a four level Rb Rydberg atom system to detect the terahertz (THz) waves with the frequency of 0.17 THz under room temperature and simulate the factors that influence the detection of THz waves. The simulation results show that the Aulter- Townes splitting interval in the electromagnetically induced transparency spectrum is proportional to the applied THz electric field intensity, and the sensitivity of the detection system is higher than that of the existing room temperature THz detectors.
With the rapid advancement of terahertz (THz) technology, there is an urgent demand for highly sensitive, broadband THz detectors that can operate at room temperature to support the evolving applications. Due to the high sensitivity of Rydberg atoms to external electric fields, detectors based on Rydberg quantum coherence offer great potential for highperformance THz detection. This paper proposed a ambient temperature electrometry approach for THz detection using probe laser spectroscopy of Rb Rydberg atoms and carry out a comprehensive study of a four-level system involving electromagnetically induced transparency (EIT) and Autler-Townes (AT) splitting in Rb cascades. By solving the Lindblad master equation, the influences of the THz electric field, probe laser, and coupling laser on the populations of the ground and Rydberg states were analyzed. Furthermore, the effects of temperature and vapor cell dimensions on the Rb atomic density are examined, revealing their critical impact on detection sensitivity. The results predict that the proposed quantum coherence based THz detection method can achieve a sensitivity as low as 10
−9V/m/Hz
1/2at ambient temperature. This paper provides a solid theoretical foundation for the implementation and optimization of Rydbergatom- based quantum coherence techniques for high-sensitivity, ambient temperature THz wave detection.