Low bending loss metal waveguide embedded in a free-standing multilayered polymer film

Very low vertical bending loss is demonstrated in a flexible metal waveguide. The waveguide consists of an 8 nm-thick and 68 mm-long Ag strip embedded in a free-standing multilayered low-loss polymer film. The polymer film is composed of a 10 mu m-thick inner cladding with a refractive index of 1.524, and a pair of 20 mu m-thick outer claddings which both have a refractive index of 1.514, resulting in a total thickness of 50 mu m. The measured vertical bending loss is lower than 0.3 dB/180 degrees at a wavelength of 1310 nm for the bending radii down to 2 mm. (C) 2008 Optical Society of America