Impact of Tm3+/Ho3+ co-doping on spectroscopic and laser properties of Ca3(VO4)2 single crystal

The series of Tm3+/Ho3+ co-doped vanadates based on Ca3(VO4)2 was obtained by Czochralski method. The trivalent doping ions were introduced into the melt in the form of oxides without any additional compensating impurities. The spectroscopic investigations showed anisotropic character of optical properties of the material. For optimal output mirror reflectivity of 94% the oscillation spectrum for holmium ions was measured to be centered at about 2070 nm with oscillation spectrum width of about 20-nm width at half maximum. Slope efficiency 5% for Ho3+ ions under 792 nm thulium pumping was obtained. Broadband tuning of Ho3+ ions oscillation wavelength within 2020–2115 nm spectral range was obtained in selective cavity with SiO2 filter.