脳梁を介したヒト運動機能調節の経頭蓋磁気刺激法による解明

学位の種別:課程博士University of Tokyo(東京大学

High-resolution projection image reconstruction of thick objects by hard x-ray diffraction microscopy

Hard x-ray diffraction microscopy enables us to observe thick objects at high spatial resolution. The resolution of this method is limited, in principle, by only the x-ray wavelength and the largest scattering angle recorded. As the resolution approaches the wavelength, the thickness effect of objects plays a significant role in x-ray diffraction microscopy. In this paper, we report high-resolution hard x-ray diffraction microscopy for thick objects. We used highly focused coherent x rays with a wavelength of ∼0.1 nm as an incident beam and measured the diffraction patterns of a ∼150-nm -thick silver nanocube at the scattering angle of ∼3°. We observed a characteristic contrast of the coherent diffraction pattern due to only the thickness effect and collected the diffraction patterns at nine incident angles so as to obtain information on a cross section of Fourier space. We reconstructed a pure projection image by the iterative phasing method from the patched diffraction pattern. The edge resolution of the reconstructed image was ∼2 nm, which was the highest resolution so far achieved by x-ray microscopy. The present study provides us with a method for quantitatively observing thick samples at high resolution by hard x-ray diffraction microscopy. © 2010 The American Physical Society.Yukio Takahashi, Yoshinori Nishino, Ryosuke Tsutsumi, Nobuyuki Zettsu, Eiichiro Matsubara, Kazuto Yamauchi, and Tetsuya Ishikawa. Phys. Rev. B 82(21), 214102 (2010)