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arXiv · 2203.04941

Vanadium doped beta-Ga2O3 single crystals: Growth, Optical and Terahertz characterization

Maneesha Narayanan·Ajinkya Punjal·Emroj Hossain·Shraddha Choudhary·Ruta Kulkarni·S S Prabhu Arumugam Thamizhavel·Arnab Bhattacharya
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Abstract

We report the growth of electrically-resistive vanadium-doped beta-Ga2O3 single crystals via the optical floating zone technique. By carefully controlling the growth parameters V-doped crystals with very high electrical resistivity compared to the usual n-type V-doped beta-Ga2O3 (ne~10^(18)/cm^3) can be synthesized. The optical properties of such high resistive V-doped b-Ga2O3 are significantly different compared to the undoped and n-doped crystals. We study the polarization-dependent Raman spectra, polarization-dependent transmission, temperature-dependent photoluminescence in the optical wavelength range and the THz transmission properties in the 0.2 - 2.6 THz range. The V-doped insulating Ga2O3 crystals show strong birefringence with refractive index contrast Dn of 0.3+-0.02 at 1 THz, suggesting it to be an ideal material for optical applications in the THz region.

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Maneesha Narayanan, Ajinkya Punjal, Emroj Hossain, Shraddha Choudhary, Ruta Kulkarni, S S Prabhu Arumugam Thamizhavel, Arnab Bhattacharya. 2022-03-09. Vanadium doped beta-Ga2O3 single crystals: Growth, Optical and Terahertz characterization. https://arxiv.org/abs/2203.04941

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