Self-Pulsed Nanosecond 2.7- $\mu\text{m}$ Solid-State Erbium Laser by Cooperatively Enhanced Reabsorption

The nanosecond self-pulsing operation of a midinfrared solid-state laser with no additional passive absorbers is reported in this paper. A proof-of-principle demonstration of the cooperatively enhanced reabsorption method, in which two laser-diode-pumped erbium gain media share the same laser resonator, is proposed. The two excited media act cooperatively to enhance the reabsorption effect and amplify the generated signal pulses. Under the pump power of 3.8 W, pulses with a pulse repetition rate of 6.2 kHz, an average output power of 107 mW, and a single pulsewidth of 185 ns are obtained.