Diode-pumped Dy:KPb₂Cl₅ laser in the middle-infrared spectral region

A Dy:KPb₂Cl₅ (KPC) laser oscillating at approximately 4.4 µm under diode laser pumping at 1.7 µm is demonstrated for the first time. A maximum output pulse energy of 1.1 mJ was achieved at 10 mJ of absorbed pump energy. Tunable laser oscillation in the 4.2-4.5 µm spectral range was recorded with this crystal. Limitations of Dy:KPC for laser oscillation due to its challenging thermo-optical properties are discussed. This crystal is a further addition to the range of low-phonon-energy materials doped with Dy ions that can be applied for laser oscillation in the mid-infrared spectral range under direct diode laser pumping.