| abstract |
An optical device includes a 6H or 4H poly type vanadium compensated silicon carbide (SiC) single crystal of high resistivity configured to transmit light having a wavelength in the range of 420 nm to 4.5 µm. The device can include a window, lens, prism, or waveguide. An optical transmission system includes a light source for generating light having a wavelength in a range of 420 nm to 4.5 µm and an optical device for receiving and transmitting the light, the optical device being a vanadium-compensated SiC single crystal with high resistivity of the 6H or 4H polytype. The disclosure also relates to crystals and methods for optical applications, including an aluminum doped SiC crystal with residual nitrogen and boron impurities, in which the aluminum concentration is greater than the combined concentrations of nitrogen and boron, and in which an optical absorption coefficient is less than about 0.4 cm -1 at a wavelength between about 400 nm to about 800 nm. |