Excitation of high-angular-momentum Rydberg states in a room-temperature alkali-atom vapor for electric-field sensing

High-angular-momentum (high-L) Rydberg states are attractive for fundamental physics and electric-field metrology. In this presentation, we describe the preparation and analysis of Rydberg states with L quantum numbers of up to 6 in a room-temperature vapor-cell setup. The excitation scheme combines optical and microwave fields, and the detection utilizes Rydberg electromagnetically-induced transparency (EIT). We study the dependence of the obtained EIT signal on frequency and power of the applied microwaves. Numerical calculations agree well with the experimental observations. The high-angular-momentum Rydberg states are utilized for measurements of DC electric fields induced via photo-illumination of the vapor-cell wall. Fields in the range of 10 V/m and above are detected in the proof-of-principle experiments. Optical methods to excite high-L Rydberg states are of general interest in high-precision spectroscopy, and Rydberg-atom-based spectroscopic electric-field sensing is applicable to plasma-field diagnostics.