skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Waveguide-Based Off-Axis Holography with Hard X Rays

Abstract

We present an off-axis holography experiment based on the coherent cone beams emitted from a pair of x-ray waveguides. A magnified off-axis hologram is recorded, from which the phase of the optical transmission function of a sample is obtained by digital holographic reconstruction. A spatial resolution of about 100 nm has been achieved at 10.4 keV photon energy. Spatial resolution is determined by the cross-sectional dimensions of the waveguide and could approach a fundamental limit of about 10 nm in future experiments. In addition, we propose a new experimental setup that might overcome this limitation.

Authors:
; ;  [1]
  1. Institut fuer Roentgenphysik, Georg-August-Universitaet Goettingen, Friedrich-Hund-Platz 1, 37077 Goettingen (Germany)
Publication Date:
OSTI Identifier:
20861526
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 97; Journal Issue: 25; Other Information: DOI: 10.1103/PhysRevLett.97.254801; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; HARD X RADIATION; HOLOGRAPHY; KEV RANGE 10-100; LIGHT TRANSMISSION; PHOTON EMISSION; PHOTONS; SPATIAL RESOLUTION; WAVEGUIDES

Citation Formats

Fuhse, C., Ollinger, C., and Salditt, T.. Waveguide-Based Off-Axis Holography with Hard X Rays. United States: N. p., 2006. Web. doi:10.1103/PHYSREVLETT.97.254801.
Fuhse, C., Ollinger, C., & Salditt, T.. Waveguide-Based Off-Axis Holography with Hard X Rays. United States. doi:10.1103/PHYSREVLETT.97.254801.
Fuhse, C., Ollinger, C., and Salditt, T.. Fri . "Waveguide-Based Off-Axis Holography with Hard X Rays". United States. doi:10.1103/PHYSREVLETT.97.254801.
@article{osti_20861526,
title = {Waveguide-Based Off-Axis Holography with Hard X Rays},
author = {Fuhse, C. and Ollinger, C. and Salditt, T.},
abstractNote = {We present an off-axis holography experiment based on the coherent cone beams emitted from a pair of x-ray waveguides. A magnified off-axis hologram is recorded, from which the phase of the optical transmission function of a sample is obtained by digital holographic reconstruction. A spatial resolution of about 100 nm has been achieved at 10.4 keV photon energy. Spatial resolution is determined by the cross-sectional dimensions of the waveguide and could approach a fundamental limit of about 10 nm in future experiments. In addition, we propose a new experimental setup that might overcome this limitation.},
doi = {10.1103/PHYSREVLETT.97.254801},
journal = {Physical Review Letters},
number = 25,
volume = 97,
place = {United States},
year = {Fri Dec 22 00:00:00 EST 2006},
month = {Fri Dec 22 00:00:00 EST 2006}
}
  • Off-axis electron holography was used to investigate the barrier profile of the Py/AlO{sub x}/ZrO{sub y}/Py magnetic tunnel junctions with different ZrO{sub y} thicknesses. The tunneling magnetoresistance (TMR) has a strong dependence on bias voltage and the bias voltage for maximum TMR is shifted from zero. This shift increases with ZrO{sub y} barrier thickness due to the increasing barrier asymmetry in the junctions. The evolution of barrier asymmetry was directly observed by the phase change of the off-axis electron holography, which unambiguously shows the barrier profile changes from triangular to trapezoidal shape as increasing of ZrO{sub y} thickness.
  • The modification of a scintillation spectrometer so that it may bc rotated about two mutually perpendicular axes is described. This arrangement greatly simplifies measurements and subsequent integration of scattered spectra at points which do not lie on axes of radial symmctry. This apparatus was used to measure scattered spectra at points at the center and near the edge of beams of 140 and 280 kvp radiation. For each point spectral distributions were measured for 30 different directions. These were then integrated to obtain the spectrum incident from all angles. These spectra were compared with those calculated using a Monte Carlomore » method. (auth)« less
  • Nearly spherical voids, with a size on the order of some tens of nanometers, are defects that have recently attracted a renewed interest, due to their capability to getter impurities and point defects in silicon. High-resolution electron holography is employed here to study the three-dimensional configuration of nearly spherical cavities obtained by 100 keV P+ ion bombardment of a silicon wafer using an ion beam with a power density of about 40 W/cm{sup 2} for 4 sec. Reconstructed phase maps have been used to obtain the qualitative topography of the cavity shape as well as quantitative measurements of the depthmore » variations. Faceting of the nearly spherical voids is discussed in detail.« less
  • Si nanowires (NWs) with axial p-n junctions were grown by the vapor-liquid-solid method. Transmission electron microscopy and electron holography were used to characterize the microstructure and electrostatic properties. Measurement of the potential profile showed the presence of a p-n junction with a height of 1.0┬▒0.3V. A Schottky barrier was observed at the end of the NW due to the Au catalyst particle. Comparison with simulations indicated dopant concentrations of 1019cm-3 for donors and 1017cm-3 for acceptors. These results confirm the benefit of combining off-axis electron holography with simulations for determining localized information about the electrically active dopant distributions in nanowiremore » structures.« less
  • The successful operation of rechargeable batteries relies on reliable insertion/ extraction of ions into/from the electrodes. The battery performance and the response of the electrodes to such ion insertion and extraction are directly related to the spatial distribution of the charge and its dynamic evolution. However, it remains unclear how charge is distributed in the electrodes during normal battery operation. In this work, we have used offaxis electron holography to measure charge distribution during lithium ion insertion into a Ge nanowire (NW) under dynamic operating conditions. We discovered that the surface region of the Ge core is negatively charged duringmore » the core-shell lithiation of the Ge NW, which is counterbalanced by positive charge on the inner surface of the lithiated LixGe shell. The remainder of the lithiated LixGe shell is free from net charge, consistent with its metallic characteristics. The present work provides a vivid picture of charge distribution and dynamic evolution during Ge NW lithiation and should form the basis for tackling the response of these and related materials under real electrochemical conditions.« less