Nanosecond room-temperature Fe : ZnSe laser pumped inside the resonator of a transversely diode-pumped Er : YLF laser

Lasing at room temperature is obtained in a Fe : ZnSe crystal installed as a passive Q-switch in a diode-pumped Er : YLF laser resonator. A miniresonator of the Fe : ZnSe laser is formed by mirrors pressed against the optical surfaces of the crystal with high reflectivities at λ = 4–4.5 μm and a high transmittance for the Er : YLF laser generation lines. In the Er : YLF laser resonator, short pulses of ~100 ns duration at λ = 2.65 μm are generated, stipulated by passive Q-switching of the resonator by the Fe : ZnSe crystal. The absorption of the Er : YLF laser radiation in the Fe : ZnSe crystal leads to the pumping of Fe : ZnSe laser, which generates pulses with a duration of less than 50 ns and an energy of ~0.5 μJ at λ = 4.2 μm. The laser operates in the pulse-periodic pump regime with a repetition rate up to 200 Hz.