Index of Refraction and Strain Induced Birefringence of Pseudomorphic Si1-xGex

The index of refraction of pseudomorphic Si1-xGex layers grown on Si has been determined at wavelengths 7n=1330 nm and 7n= 1550 nm, for Ge concentrations between x=0.01 and x=0.1. The refractive index values were obtained from mode profile measurements on a series of Si1-xGex waveguides. The index of refraction is significantly larger for light polarized parallel to the growth direction than for light polarized in the plane of the epilayer. …