Measurement of Alkali Concentration in Dioded Pumped Alkali Vapor Lasers by 100 GHz Spectral Scanning

Atmospheric transmission calculation of diode‐pumped alkali laser energy transfer

“…In addition, due to the inherent properties of molecules and their interactions with the external environment, any molecular absorption spectrum exhibits a spectral line broadening around its center wavelength that follows a certain line shape rule, as mentioned in formula (2). Considering the atmospheric pressure characteristics of the actual atmosphere, the Doppler broadening in the gas system is far less than the collision broadening, so it can be assumed that the line shape of molecular absorption spectra in the atmosphere can be characterized using a Lorentzian line shape 16–20 : $$${f}_{L}(\lambda )=\frac{1}{\pi }\times \frac{{\gamma }_{L}}{{(\lambda -{\lambda }_{0})}^{2}+{{\gamma }_{L}}^{2}},$$$where $${\gamma }_{L}$$ is the half width at half maximum of the Lorentz line shape.…”

“…Laser wireless energy transmission technology is more suitable for long‐distance air and environments that are sensitive to electromagnetic interference, such as remote charging of unmanned aerial vehicles and energy transmission for outer spacecraft. Diode‐pumped alkali laser (DPAL) is considered as the most promising lasers for application in laser long distance energy transfer due to their high atmospheric transmission efficiency, excellent beam quality, good matching of wavelengths with the response range of Si and GaAs photovoltaic cells that can achieve high photoelectric conversion efficiency, 15–17 and high enough output power potential 18 . DPAL laser energy transfer efficiency is affected by various components, including the electro‐optical conversion rate of the laser, antenna emission/receiving efficiency, laser transmission efficiency in the atmosphere, and the photoelectric conversion rate of photovoltaic cells.…”