Y. Ran et Jy. Qin, The gain coefficient of optically pumped NH3 molecules far-infrared laser in vibration ground state, J INF M W, 19(3), 2000, pp. 229-232
The density matrix equation of three-level system for NH3 molecules far-inf
rared (FIR) Raman transition in vibration ground state was solved. The gain
coefficient of NH3 molecules far-infrared laser in vibration ground state
was obtained.