Study on Effects of Pump Source on Spectra of Optically Pumped Sub-Millimeter Wave Laser

摘要

According to the three-energy-level model, the operating gas molecules on vibrational ground-state energy level El absorbed the pumping energy and transited to vibrational exited-state upper-level E3, pure rotational transition between E3 and vibrational exited-state lower-level E2 and emitted SMMW laser. In order to occur to SMMWL emissions, the pump source laser must satisfy the following conditions: enough strength to counteract the absorption effect; resonant or near-resonant to vibrational absorb transition of operating gas molecules. On the other hand, the practical pump source was not homochromatic, so its spectral broadening must be considered. In this paper, effects of pump source laser on SMMWL spectra including pump power intensity, pump frequent offset and pump spectral broadening were studied, with TEA CO{sub}2-9R(16) pumped NH{sub}3 90.4μm laser used to be an example.