In this paper, the design of the infrared beamline BL01B at Shanghai Synchrotron Radiation Facility (SSRF) has been preformed. The present status of this beamline will be described. This beamline is under construction. It utilizes both edge radiation and bending magnet radiation by using a unique extraction optics system. The expected performances of the beamline have been discussed. Moreover, the endstations and main research fields have been described.
The optical and dielectric properties of NaCl and alkali halide are studied by Terahertz time-domain spectroscopy (THz-TDS) technique from 0.3 THz to 1.4 THz. The absorption spectral features of measured samples are discussed based on their characteristic and common features. Further, the measured complex refractive index and dielectric functions of NaCl are well fitted by a standard Lorentz model. Theoretical calculations indicate that characteristic phonon resonance of NaCl is dominated by the transverse optical phonon mode at 5.10 THz.