Mid-infrared thermal detector based on Au-disk structure and vanadium dioxide

In order to enhance the absorption of phase change materials in specific spectral range, a novel compact structure based on surface plasmon resonance is proposed, which is composed of vanadium dioxide (VO2) film and Au-disk structure. Simulation results show that the absorption peak at lambda=4.0 mu m with the full width at half maximum is only about 100nm, and the dependence on the structure parameters are analyzed in detail. Because the resistivity changes greatly during the phase transition of VO2, the detection of a specific spectrum can be completed by signal detection. Our study can be used in the development of new mid-infrared thermal detectors and active control devices.