Thermal tunable one-dimensional photonic crystals containing phase change material

• Published in: Chinese physics B Vol. 29; no. 10; p. 104210
• Main Authors: Jia, Yuanlin, Ren, Peiwen, Fan, Chunzhen
• Format: Journal Article
• Language: English
• Published: 01.09.2020
• ISSN: 1674-1056
• DOI: 10.1088/1674-1056/abab78

To obtain the adjustable photonic crystals (PCs), we numerically investigate one-dimensional (1D) PCs with alternating VO 2 and SiO 2 layers through transfer matrix method. The dispersion relation agrees well with the transmittance obtained by the finite element calculation. Tunable band gaps are achieved with the thermal stimuli of VO 2 , which has two crystal structures. The monoclinic crystal structure VO 2 (R) at low temperature exhibits insulating property, and the high temperature square rutile structure VO 2 (M) presents metal state. Concretely, the bandwidth is getting narrower and red shift occurs with the higher temperature in VO 2 (R)/SiO 2 PCs structure. Based on the phase change characteristics of VO 2 , we can flexibly adjust the original structure as VO 2 (R)/VO 2 (M)/SiO 2 . By increasing the phase ratio of VO 2 (R) to VO 2 (M), the band gap width gradually becomes wider and blue shift occurs. The discrete layers of gradient composites on the dispersion of 1D PCs are also investigated, which enhances the feasibility in practical operation. Thus, our proposed thermal modulation PCs structure paves a new way to realize thermal tunable optical filters and sensors.