Fabrication and optical properties of organic crystal waveguide

摘要

A ridge waveguide of an organic salt, 4-N, N-dimethylamino-4'-N-methyl-stilbazorium tosylate, DAST, which has the largest second-order optical nonlinearities among organic materials, was fabricated for the first time to our knowledge. DAST crystal was covered by poly (methyl methacrylate) as a protect layer for a photo-resist solution, then standard photlithography and oxygen reactive ion etching (RIE) processes were applied. DAST ridge waveguide, 34x20 umm and 6x6 umm channel s with 2mm in length were successfully fabricated by this process. To reduce the refractive index of the crystal, photo bleaching was effectively applied for DAST crystla. So. Photobleaching can be applied to fabricate a cladding layer for the ridge waveguide.