We present temperature-dependent refractive index along crystallographic b[010] and a direction perpendicular to (100)-plane for monoclinic phase (β) Ga(2)O(3) single crystal grown by the optical floating zone technique. The experimental results are consistent with the theoretical result of Litimein et al.1. Also, the Sellmeier equation for wavelengths in the range of 0.4-1.55 μm is formulated at different temperatures in the range of 30-175 °C. The thermal coefficient of refractive index in the above specified range is ~10(-5)/°C.

No abstract

No abstract

Here we address the issue of growing single crystals of Nd and Cr codoped YVO 4 , a promising self Qswitching laser material, in different oxygen partial pressures. Single crystals of 1.4% Cr and 0.7% Nd codoped were grown by the optical floating zone (OFZ) technique. Our findings emphasize, as the oxygen content in the growth atmosphere is increased, the absorption band corresponding to 2 A 1 → 2 B 2 transition of Cr 5+ , which participates in self-Q-switching, improves significantly. Similarly, a significant improvement is observed in the present case in comparison to that grown by the Czochralski method in 2% oxygen by Pan et al. [Opt. Express 2012, 20, 2178. Crystals grown by the OFZ technique contain fewer oxygen vacancies that inhibit the tendency of Cr ions to get reduced to the undesired +3 state. Red shift in the band gap energy is observed due to the incorporation of Nd, whereas Cr does not influence the band gap energy.

No abstract