The optimum pumping power for optically pumped FIR lasers

摘要

The relations between the output power of optically pumped FIR laser and the pumping power were studied theoretically by solving the density matrix equation of four level system by means of the matrix signal flow graph method. The output power density of FIR laser was. calculated by the iterative method. A set of curves of output FIR laser power density against pumping power has been obtained. It has found that every such curve has a maximum point of which the position is different for different pumping detuning. According to these results we predicted that there would exist an optimum power density for an optically pumped FIR laser with certain pumping detuning. This theoretical result would help us to design the optically pumped FIR lasers.