We report on the influence of temperature on the polarization behavior of highly oriented ZnO thin film. First, the investigation of crystal structure change is studied, providing supporting information on the macroscopic-scale polarization of the ZnO thin film. Here, the lattice distortion is investigated by using X-ray diffraction. Furthermore, the role of temperature on the polarization behavior of the ZnO thin film is comprehensively studied by using temperature dependent spectroscopic ellipsometry. Here, the temperature dependent dielectric function analysis and electronic excitation models are used to understand the mechanism of polarization. We found an interesting temperature dependence of electronic transition, where the red-shift absorption and exciton-phonon interaction are observed on the system. This interaction is responsible for the increase of polarization response, which is confirmed by dielectric susceptibility spectra. These results provide important understanding for the control of the polarization dependence on the working temperature of ZnO thin film, which is the essential key in the fabrication of switchable optical devices.

We report on the effect of the morphological modification on optical properties and polarization of ZnO nanorods (NR). Here, the morphology and structure of the ZnO NR were modified by introducing different annealing temperatures. The increase of length and diameter and change in density of the ZnO NR were clearly observed by increasing the annealing temperature. We found that the samples show different oxygen vacancy (V_O) and zinc interstitial (Zn_I) concentrations. We suggest that the different concentrations of V_O and Zn_I are originated from morphological and structural modification. Our results reveal that optical absorption and polarization of ZnO NR could be enhanced by producing a high concentration of V_O and Zn_I. The modification of V_O and Zn_I promotes a decrease in the band gap and coexistence of high optical absorption and polarization in our ZnO NR. Our findings would give a broad insight into the morphological modification and characterization technique on ZnO NR. The high optical and polarization characteristics of ZnO NR are potential for developing the high-performance nanogenerator device for multitype energy harvesting.