• A. Rajasri
• G. S. Kumar
• P. Manoher

Yttrium Ortho Vanadate (YVO4) is a positive uniaxial, wide transparency range optical fiber material with large birefringence. The variation of refractive indices near the surface of YVO4 optical fibers is observed. The “Local” fields experienced by ions near the surface of fiber material are different from those in the interior. Using theoretical Point Dipole Approximation (PDA), one can calculate refractive index variation near the surface of the material. In thin films and optical waveguides, this variation can alter the propagation characteristics. The variation of ordinary and extraordinary refractive indices no and ne from the surface to a depth of 71.2Å near the surface for Z-cut and X-cut YVO4 waveguides are evaluated using PDA. For a Z-cut waveguide, no is found to increase from surface to the interior whereas ne is found to decrease from surface to the interior. For an X-cut, Z-propagation waveguide, no is found to decrease from the surface to the interior whereas, ne is found to increase from the surface to the interior. It is observed that the refractive indices no, and ne variation and also the birefringence (dn= ne -no) variation with depth near the surface for both the cases are quite opposite in nature.

Point Diople Approximation, refractive index, birefriengence, YVO4 waveguide, thin film

"Study of Refractive Index Profile near the Surface of YVO4 Waveguide using Point Dipole Approach", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.8, Issue 9, page no.d74-d81, September-2021, Available :http://www.jetir.org/papers/JETIR2109306.pdf

"Study of Refractive Index Profile near the Surface of YVO4 Waveguide using Point Dipole Approach", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.8, Issue 9, page no. ppd74-d81, September-2021, Available at : http://www.jetir.org/papers/JETIR2109306.pdf