Bi-Hsuan Lin
National Synchrotron Radiation Research Center, Taiwan
Title: Temperatureâ€dependent hard Xâ€ray excited optical luminescence to study the optical properties of the ZnO microwires
Biography
Biography: Bi-Hsuan Lin
Abstract
The advantages of using synchrotron radiation as the excitation source are that the tunable X-ray energy allows the preferential excitation of the elements through the X-ray absorption edges, and a suitable time structure of the synchrotron can be used to study the dynamics of luminescence of the materials. We develop the synchrotron based hard X-ray excited optical luminescence (XEOL) and time-resolved X-ray excited optical luminescence (TR-XEOL) at the X-ray Nanoprobe (XNP) facility at Taiwan Photon Source (TPS). In parallel to the construction of the XNP endstation, demonstrative XEOL experiments were conducted by unfocused X-ray beam at Taiwan Light Source (TLS). The low temperature (4.2K) and temperature-dependent XEOL with X-ray excited energy below, at and above the Zn K-edge (9.659keV) were used to obtain the further information of the optical mechanisms of the ZnO microwires. The temperature-dependent XEOL behavior of the ZnO microwires with X-ray energy at 9.67 keV was shown in Figure 1. The free A excitons, donor bound excitons and their phonon replicas can be seen unambiguously at low temperatures. The design of the XEOL and TR-XEOL at XNP and the demonstrative experimental results will be reported.
