BL1B Terahertz Spectroscopy Using Coherent Synchrotron Radiation
Description
Coherent synchrotron radiation (CSR) is a powerful light source in the terahertz (THz) region. This beamline has been constructed for basic studies on the properties of THz-CSR. However, it can be also used for measurements of reflectivity and transmission spectra of solids using conventional synchrotron radiation. The emitted THz light is collected by a three-dimensional magic mirror (3D-MM, M0) of the same type as those already successfully installed at BL43IR in SPring-8 and BL6B in UVSOR-II. The 3D-MM was installed in bending magnet chamber #1 and is controlled by a 5-axis pulse motor stage (x, z translation; θx, θy, θz rotation). The acceptance angle was set at 17.5 – 34 degrees (total 288 mrad) in the horizontal direction. The vertical angle was set at ±40 mrad to collect the widely expanded THz-CSR. The beamline is equipped with a Martin-Puplett type interferometer (JASCO FARIS-1) to cover the THz spectral region from 4 to 240 cm-1 (hν = 500 μeV – 30 meV). There is a reflection/absorption spectroscopy (RAS) end-station for large samples (~ several mm). At the RAS end-station, a liquid-helium-flow type cryostat with a minimum temperature of 4 K is installed.


Fig. 2. Obtained intensity spectra with the combination of a light source (UVSOR), interferometer (FARIS-1), and detectors (Si bolometer and InSb hot-electron bolometer)
Technical Data
| Interferometer | Martin-Puplett (JASCO FARIS-1) |
| Wavenumber range (Energy range) | 4-240 cm-1 (500 μeV-30 meV) |
| Resolution in cm-1 | 0.25 cm-1 |
| Experiments | Reflection/transmission spectroscopy |
| Miscellaneous | Users can use their experimental system in this beamline. |



