Efficient lasing in a Fe²⁺:ZnSe crystal at room temperature

Abstract

Efflcient room-temperature lasing is obtained in a Fe ^: ZnSe crystal pumped by 2.9364-цт giant pulses from an Er: YAG laser. The slope efficiency of a Fe ^ : ZnSe laser with respect to the absorbed pump energy is 13 %. The laser with a dispersion resonator can be continuously tuned from 3.95 to 5.05 цт. The luminescence lifetime of the T2 level of the Fe ^ ion in a ZnSe matrix at room temperature is measured to be 355 ± 15 ns.

Progress in Cr2+and Fe2+doped mid‐IR laser materials

“…Tunable oscillation of the Fe:ZnSe was demonstrated with diffraction grating in the Littrow cavity [14] and with a CaF 2 dispersive prism [11,86]. The achieved tuning curve shown in Fig.…”

“…Below we will focus on several non-traditional regimes of oscillation of the Cr 2+ lasers. Pulsed, tuning range, μm 2.26-3.61 [74] Pulsed, energy mJ 17@300 μs [74] Fe:ZnSe Pulsed @150 K, energy, μJ 5 [13] Pulsed @85 K, energy, mJ 187 @300 μs [11,85] Pulsed, efficiency,% 43 [11,85] Microchip gain-switched @300 K, energy, μJ 1 @ 5 ns [14] Gain-switched @300 K, energy, mJ 0.4 @60 ns [11,86] Gain-switched @300 K, tuning range, μm 3.95-5.05 [11,86] CW, output power, 150 mW @4.06 μm [87] 5. Non traditional lasing regimes of the Cr 2+ -doped II-VI lasers…”

Room temperature high energy high efficient Fe²+:ZnSe laser

“…Among all of Fe 2+ -doped II-VI crystal laser, Fe 2+ :ZnSe is most efficient, Much attention has been devoted to the high-energy pulsed Fe 2+ :ZnSe laser [3] . For example, the highest energy of Fe 2+ :ZnSe laser E=2.1J with 35% efficiency has been demonstrated by Frolov [4] at a temperature T= 85 K. However, the Fe 2+ :ZnSe laser energy is only 42mJ with a poor efficiency ab =1% at room temperature due to the life time of upper laser state 5 T2 of Fe 2+ ion sharply reducing with elevated temperature, it is 360ns at room temperature [5] . It is necessary to pump Fe 2+ :ZnSe laser with a Q switched solid state laser for high efficiency at room temperature, but the maximal energy of Q switched solid state laser at 3 m wavelength range is only 35mJ.…”

Room temperature high energy Fe:ZnSe laser pumped by non-chain pulsed HF laser

“…For example, the highest energy of Fe:ZnSe laser E=2.1J with 35% efficiency has been demonstrated by Frolov at a temperature T= 85 K. However [6] , the Fe:ZnSe laser energy is only 42mJ with a poor efficiency η ab =1% at room temperature due to the life time of upper laser state 5 T 2 of Fe 2+ ions sharply reducing with elevated temperature. At room temperature the life time of upper laser state is only 360ns [7] . It is necessary to pump Fe:ZnSe laser with a Q switched solid state laser for high efficiency at room temperature, but the maximal energy of Q switched solid state laser at 3μm wavelength range is only 35mJ.…”