A stable, narrow-linewidth laser system with broad frequency tunability and fast switching time

To change the sensing frequency of a Rydberg atom-based sensor, adjustments to the wavelength of the Rydberg state excitation laser are necessary, with required wavelength shifts on the order of 10 nm. To efficiently change the sensing frequency, a laser with a narrow linewidth and broad tuning capability is essential. In this talk, we present a narrow linewidth laser system capable of swiftly altering a coupling laser wavelength by up to 8 nm in less than 50 μs. The laser system comprises a frequency-stabilized continuous wave laser and an electro-optic frequency comb. An individual comb line is selected using a filter, and a high-speed electro-optic modulator is employed to tune the chosen comb line to a specific frequency. Through Rydberg atom-based sensing experiments, we demonstrate frequency hopping between two Rydberg states with a rapid switching time of 400 μs, limited by the radio frequency electronics. The switching time can be further reduced to approximately 50 μs with a ping-pong scheme. If updating the radio frequency is not required during frequency hopping, the switching can be done in 200 ns. These findings showcase the potential of our laser system for advanced applications in Rydberg atom-based radio frequency sensing, like communications and radar.