Sensor of small movements, based on one-dimensional photonic crystal with defect

The results of computer simulation of optical properties of one-dimensional (1D) photonic crystal (PC) with defect, based on the layers Si–SiO$_2$ in near IR range are presented. The optical thicknesses of layers, which form PC, were $\lambda$/4, 3$\lambda$/4 and 10$\lambda$/4. Defect was formed by air gap in the middle of PC. The influence of defect thickness on spectral position of the transmission band of defect was studied. It was shown that the sensitivity on the defect thickness $d$ is in the range of $\Delta\lambda/\Delta d$ = 330–1200 nm/$\mu$m and 0.6–0.85 dB/nm, depending on sensor geometry and measurement method. This makes 1D PC with defect promising for the use as sensitive element in sensors of small movements.