Impact of light-induced atomic desorption on electric field sensing via electromagnetically induced transparency and...

In Rydberg quantum electric field sensing, the amplitude and linewidth of electromagnetically induced transparency (EIT) spectra significantly impact the accuracy of electric field measurements. This paper discusses the influence of atomic density on the amplitude and linewidth of EIT spectra in a vapor cell within a three-level ladder system driven by two-photon excitation. Due to the adsorption of alkali metal atoms on the inner surface of the vapor cell, the study utilizes light-induced atomic desorption effects to regulate the atomic density using LED light. This approach, combined with probe and coupling lasers, results in the formation of high-amplitude, low-linewidth EIT spectra. Based on the Rydberg atom sensing measurement system constructed in this study, when the number of atoms per cubic meter is less than 1.5×10²⁴, a decrease in the optical depth at the bottom of the EIT leads to a reduction in amplitude and an increase in linewidth. When the number of atoms per cubic meter exceeds 4×10²⁴, a decrease in the peak value at the top of the EIT results in a reduction in amplitude, with a slight decrease in linewidth. By adjusting the atomic density within the vapor cell through the power of desorption light and optimizing the laser Rabi frequency parameters, the atomic number density is maintained between 1.5×10²⁴ and 4×10²⁴ per cubic meter, yielding high-amplitude, low-linewidth EIT spectra. Additionally, the influence of introducing 365 nm desorption light on the accuracy of the constructed electric field measurement system is analyzed and corrected.