Fabrication of low-cost thermo-optic variable wave plate based on waveguides patterned on di-ureasil hybrids

Abstract

An integrated variable wave plate device based on a thermo-optic (TO) effect was fabricated by patterning a waveguide channel through direct UV laser writing on the surface of sol-gel derived organic-inorganic hybrid (di-ureasil) films. The di-ureasil layer is stable up to 250 degrees C and has a high TO coefficient calculated as -(4.9 +/- 0.5) x 10(-4) degrees C-1 at 1550 nm. The waveguide temperature was tuned, inducing optical phase retardation between the transverse electric and transverse magnetic modes, resulting in a controllable wave plate. A maximum phase retardation of 77 degrees was achieved for a waveguide induced temperature increase of 5C above room temperature, with a power consumption of 0.4 W. The thermal linear retardation coefficient was calculated to be 19 +/- 1 degrees/ degrees C. (C) 2014 Optical Society of America.