Kati Biedermann

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A new method to grow bulk quantities of single-walled carbon nanotubes (SWCNTs) by a catalytic chemical vapor deposition (CVD) process with the possibility of varying the pressure has been developed and is reported in this paper. Thermal decomposition of ferrocene provides both catalytic particles and carbon sources for SWCNT growth using Ar as a carrier(More)
By means of the Multiple-Sine-Slit Microdensitometer (MSSM), MTF's up to 1500 c/mm have been evaluated for five photographic plates for holography, Agfa-Gevaert Scientia 10E75, 8E75, 8E75B, and Kodak 649-F and Type 120-02. For comparison, an as-if-MTF has also been derived from diffraction efficiency measurements. In addition sensitivity at lambda = 633 nm,(More)
The moving aperture and the moving random mask are two methods suggested for speckle reduction in recording images of diffuse objects with coherent light. An analysis is given that shows that these methods are equivalent to a two-step recording process: (1) recording the image with the full pupil in coherent light and (2) reimaging and recording this(More)
A detailed analysis is made of a system for fringe evaluation in hologram interferometry in which a conjugate reconstruction beam scans the hologram, and the resulting fringe motion is observed in the real image of the object. The factors decisive for best use of the system are studied, especially the sensitivity and accuracy of the measurements and their(More)
In this experimental work we present novel methods to increase the spatial resolution of valence electron energy loss spectrometry (VEELS) investigations below the limit given by the inelastic delocalization. For this purpose we analyse a layer stack consisting of silicon/silicon-oxide/silicon-nitride/silicon-oxide/silicon (SONOS) with varying layer(More)
The holographic exposure index (HEI) relates the radiant energy necessary for recording a hologram to the diffraction efficiency to be achieved. In addition to the sensitometric speed of the recording material, the HEI takes into account that the modulation transfer function and macroscopic transfer characteristics, depolarization, and losses in the object(More)
The Multiple-Sine-Slit Microdensitometer (MSSM) measures transmittance modulation by scanning the sample with a sinusoidal irradiance distribution generated by laser two-beam interference. The theory of the instrument is derived both from conventional microdensitometry and from treating the sample as a complex valued grating that diffracts two impinging(More)
A system for fringe evaluation in hologram interferometry is studied in which a conjugate reconstruction beam scans the hologram, and the resulting fringe motion is observed in the real image of the object. The principle is suitable for semiautomatic evaluation. An earlier article presented a detailed theoretical analysis of the measuring principle, and the(More)
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