title: X-ray linear birefringence and linear dichroism in a cobalt crystal measured with a tunable X-ray polarimeter.
abstract: X-ray linear birefringence and linear dichroism spectra have been measured simultaneously and quantitatively for the first time. The sample was a hexagonal cobalt single-crystal foil. The apparatus used was an energy-tunable X-ray polarimeter, consisting of a polarizer, a phase retarder and an analyser. The X-ray energy was scanned over a range of 350 eV near the K-absorption edge. The Kramers-Kronig relation between the refraction and absorption anisotropy has been confirmed on an absolute scale. The phase-difference sensitivity of the polarimeter as a polarization inferometer is as small as 2pi/10000, which is about 100 times smaller than that of the Bonse-Hart inferometer.
authors.affiliation: National Research Laboratory of Metrology, 1-1-4 Umezono, Tsukuba, Ibaraki 305, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Okitsu
authors.forename: T
authors.initials: T
authors.lastname: Oguchi
authors.forename: H
authors.initials: H
authors.lastname: Maruyama
authors.forename: Y
authors.initials: Y
authors.lastname: Amemiya