Response of Axially Stressed Edge-Illuminated Holographic Gratings in PQ/PMMA Photopolymers

A free-space unslanted, edge-illuminated, tunable Bragg filter in Phenanthrenquinone doped Poly(methyl methacrylate) (PQPMMA) operating at 1550 nm has been realized with a tuning range larger than 4 nm. The grating is ~1 cm long with a rejection efficiency of ~90% and a full-width at half-maximum spectral width of ~0.35 nm in its unstressed state. The tunability of the grating was achieved by stretching and compressing the sample.