Efficient Er:YAG lasers at 1645.55 nm, resonantly pumped with narrow bandwidth diode laser modules at 1532 nm, for methane detection

Eye safe laser operation at 1645.55 nm (6077 cm(-1)) of resonantly pumped Er:YAG laser systems is demonstrated in cw and Q-switched operation. High brightness diode laser modules emitting at 1532 nm have been utilized as pump sources providing an absorption efficiency of up to 96%. This leads to an overall efficiency of the Er:YAG laser of 30%. For cw operation, 9 W output power is possible at pump power of 30 W while Q-switching results in generation of more than 7 mJ pulses with duration of 60 ns and repetition rate of 500 Hz. The Er:YAG laser systems have been applied for methane detection measurements demonstrating their feasibility for CH4-DIAL applications