Infrared Spectrum Regulation of One-Dimensional Photonic Crystal Thin Films with Ge2Sb2Te5

The active regulation of the infrared radiation is a focal point in the fields of energy saving, thermal camouflage and optical switching. In this paper, we conduct the research on broadband infrared radiation tunable films with phase change material Ge
2
Sb
2
Te
5
(GST). By utilizing the property of variable refractive index of GST, we construct the GST/ZnS one-dimensional photonic crystal films with tunable infrared emissivity. The fabricated [GST/ZnS]
⁴
film has a great switchable ability of infrared radiation with the tunable range of the emissivity in 3-5 μm waveband is 0.385. The infrared emissivity of the film is 0.159 when the GST is at crystalline state and 0.544 when the GST is at amorphous state. The broadband infrared radiation tunable film is expected to be extended to applications that rely on infrared radiation control technology, such as energy saving, thermal camouflage, and optical switching.