Structural, optical, and spectroscopic properties and efficient two-micron lasing of new Tm3+:Lu2O3 ceramics

The structural, optical, and spectroscopic properties of new Tm³⁺ : Lu₂O₃ laser ceramics are studied. The average size of a ceramic grain (crystallite) is found to be 540 – 560 nm. The absorption spectrum measured in the near-IR region shows that this ceramics can be pumped by commercially available laser diodes at wavelengths of 796 and 811 nm. The high-transmission region of the ceramics in the mid-IR region extends to 7 μm. Investigations of the luminescence spectrum in the region of 1.75 – 2.2 mm upon laserdiode pumping show strong lines peaked at wavelengths of 1942, 1965, and 2066 nm. Ellipsometric measurements yield refractive indices n ≈ 1.92 at the pump wavelength 796 nm and n ≈ 1.94 at the laser wavelength 2066 nm. Continuous-wave lasing of a Tm³⁺ : Lu₂O₃ ceramic laser at a wavelength of 2066 nm is demonstrated under diode-laser pumping at wavelengths of 796 and 811 nm.