TmYVO4

TmYVO4, or thulium-doped yttrium vanadate, is a solid-state laser crystal used as a gain medium in diode-pumped lasers. It consists of thulium ions (Tm3+) substituted on yttrium (Y3+) sites within the yttrium vanadate (YVO4) host lattice. The YVO4 host adopts a tetragonal zircon-type structure and provides a transparent, mechanically robust matrix for infrared emission.

Optical properties and transitions are dominated by the Tm3+ energy levels. The principal laser emission occurs near 2 micrometers, arising mainly from transitions such as 3F4 to 3H6. The material can be pumped efficiently with near-infrared diodes, typically around 0.8–0.9 micrometers, which excite Tm3+ ions to higher levels and allow population of the lasing state. The relatively broad emission bandwidth supports tunable operation and short-pulse generation in mode-locked configurations.

Tm:YVO4 is valued for its good optical quality, relatively strong absorption and emission cross-sections at accessible pump wavelengths, and compatibility with diode pumping. Crystals can be grown to high quality via established methods such as the Czochralski process, with doping levels chosen to balance absorption, gain, and concentration quenching.

Applications of Thulium-doped YVO4 include 2 μm solid-state lasers in continuous-wave, Q-switched, and mode-locked regimes. The 2 μm wavelength is eye-safe and useful in medical procedures, remote sensing, and materials processing. Tm:YVO4 is often considered alongside other Tm-doped hosts for systems requiring efficient diode-pumped operation and reliable thermal performance.