Frequency-Energy Characteristics of Mercury Ion RM Laser (398.4 nm)

Abstract

One of the fundamental directions in the development of lasers based on self-terminating transitions (RM transitions) in metal atoms and ions is their use in brightness amplification systems. Improvement of these systems requires expanding the operational spectral range and increasing the pulse repetition frequency. A promising approach to addressing these challenges is the use of a new class of high-speed high-frequency switches based on a slit discharge (eptrons) for pumping RM lasers, particularly those operating in the UV range. Within this approach, this paper studies the frequency-energy characteristics of a mercury ion RM laser (λ = 398.4 nm). The use of a high-speed slit-discharge switch enables generating voltage pulses with a rise time of 2–3 ns across the electrodes of a gas-discharge tube and lasing in a double-pulse mode at repetition frequencies up to 300 kHz. It is ascertained that the laser pulse energy strongly depends on temperature and pulse repetition frequency, and the optimal frequency decreases as the temperature increases. Lasing in the form of bursts of four pulses has been demonstrated. The achieved high pulse repetition frequencies of the laser radiation at the short wavelength can contribute to the creation of unique brightness amplifiers based on an Hg⁺ RM laser.