Optical bistability of partial reflection-coated thin film of oil red O

In this paper, a thin film of oil red O coated by partial dielectric mirrors (PRFORO) operating as an optical bistable device is proposed. The equation of the output-input intensity relation considering nonlinear absorption inside PRFORO is derived and the optical bistability (OB) of PRFORO is shown. Additionally, the influence of the nonlinear refractive, absorptive coefficients of oil red O (ORO), reflective coefficient of mirrors, and the thickness of thin film on the OB is numerically investigated and discussed. As a result, the threshold switching power is lower than 19 mW; the minimum power of output up-state is larger than 40 µW for the optimal PRFORO designed with an ORO concentration larger than 0.1 mM; the thickness of the thin film is longer than 0.1 mm; and the reflective coefficient of mirrors is lower than 93%. The proposed model is suitable for all-optical switches, optical images, and signal processing.