Institute for Materials Research (IMR) of Tohoku University, HORIBA Limited, and Tohoku Techno Arch Company, Limited announced on July 19, 2011 that a research group led by associate professor of IMR, Kouichi Hayashi has succeeded in 3D atomic imaging by a time-inverted version of photoelectron holography. Details were published in Physical Review Letters*.
Determination of atomic arrangement in a material will be an important step to understand its properties and to create novel advanced materials. The research group constructed an apparatus for internal-detector electron holography based on a scanning electron microscope (SEM). Using an energy-dispersive x-ray detector, an electron gun, and a computer-controllable sample stage, a multiple-energy hologram of the atomic arrangement around the Ti atom in SrTiO3 is obtained by recording the characteristic Ti Kα x-ray spectra for different electron beam angles and wavelengths.
A real-space image was obtained by using a fitting-based reconstruction algorithm SPEA-MEM. 3D atomic images of the elements Sr, Ti, and O in SrTiO3 were clearly visualized. Broadening of O-atom image is observed to show O-atom fluctuation, suggesting the ability of the present method for providing advanced information on the atomic structure analysis.
*Akio Uesaka, Kouichi Hayashi, Tomohiro Matsushita, and Shigetoshi Arai, "3D Atomic Imaging by Internal-Detector Electron Holography", Physical Review Letters, Vol. 107, No. 3, p. 045502 (2011) [4 pages]. Doi: 10,113/PhysRevLett.107.045502; published 19 July 2011.
This article first appeared in the August 2011 issue of Nanotech Japan Bulletin