A PDMS-based pressure-tunable nanograting

We report the design, fabrication, and characterization of a pressure-tunable guided-mode resonance grating. A thin, flexible polydimethylsiloxane (PDMS) membrane was fabricated with an embedded titanium dioxide (TiO2) nanograting. When pressure is applied to the device, the membrane expands, and the pitch of the grating increases; this causes a shift in its resonant wavelength. By varying the pressure by only 3500 Pa, a tunable range of over 35 nm can be observed.