Development of vacuum-ultraviolet circular dichroism measurement system using a polarizing undulator.
We have developed an improved circular dichroism (CD) and linear dichroism (LD) simultaneous measurement system for the vacuum ultraviolet (VUV) region by polarization modulation techniques using a four-period Onuki-type crossed undulator as a polarized light source. The system has been constructed at the VUV beamline BL-5 in the electron storage ring TERAS, at AIST. Our improvements, in particular the adoption of an optical chopper as the detection method of incident light, have resulted in a flat baseline and a consequent simplification of the Mueller matrix calculation for our optical system. Based on the Mueller matrix calculation, we have successfully measured real VUV-CD and LD spectra of leucine films for wavelengths down to 160 nm with absolute optical constants. The obtained spectra show good consistency with spectra measured by conventional methods.
Tanaka
Masahito
M
Research Institute of Instrumentation Frontier, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki, Japan. masahito-tanaka@aist.go.jp
Yagi-Watanabe
Kazutoshi
K
Yamada
Toru
T
Kaneko
Fusae
F
Nakagawa
Kazumichi
K