An in-line Mach-Zehnder interferometer (MZI) for simultaneous measurement of temperature and refractive index (RI) is proposed and demonstrated. The sensor is composed of cleaved taper, single-mode fiber (SMF) and spherical structure. Using precision device to measure the position of waist, the cleaved taper structure is obtained by cutting the taper structure. The sensitivities of the temperature are 0.052 nm/℃ and 0.037 nm/℃ in the temperature range of 25—70 ℃, respectively. The RI sensitivities are -56.59 nm/RIU and -43.53 nm/RIU in the RI range of 1.335—1.38, respectively. This sensor has many advantages such as compact structure and good stability.

Cu₂ZnSn(S, Se)₄(CZTSSe) thin films were deposited on flexible substrates by three evaporation processes at high temperature. The chemical compositions, microstructures and crystal phases of the CZTSSe thin films were respectively characterized by inductively coupled plasma optical emission spectrometer (ICP-OES), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman scattering spectrum. The results show that the single-step evaporation method at high temperature yields CZTSSe thin films with nearly pure phase and high Sn-related phases. The elemental ratios of Cu/(Zn+Sn)=1.00 and Zn/Sn=1.03 are close to the characteristics of stoichiometric CZTSSe. There is the smooth and uniform crystalline at the surface and large grain size at the cross section for the films, and no other phases exist in the film by XRD and Raman shift measurement. The films are no more with the Sn-related phase deficiency.