Femtosecond laser modification of 6H-SiC crystals for waveguide devices

We report on optical waveguides produced by a femtosecond laser in 6H-SiC crystals. Their guiding properties have been investigated at a wavelength of 1064nm, and confocal micro-Raman images have been obtained at an excitation wavelength of 532nm. The results demonstrate that mode profiles can be tailored by the adjustment of writing parameters, and the blueshift of the spectrum (at around 787.05cm(-1)) mainly takes place in the irradiated areas. From images of Raman intensity and spectral shift, it is obvious that optical properties in guiding regions are well preserved. These waveguides may have potential applications in integrated optics and quantum photonics.