Publications by authors named "Norman Tolk"

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The photoelastic phenomenon has been widely investigated as a fundamental elastooptical property of solids. This effect has been applied extensively to study stress distribution in lattice-mismatched semiconductor heterostructures. GaAs based optoelectronic devices (e.

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Tissue ablation with mid-infrared irradiation tuned to collagen vibrational modes results in minimal collateral damage. The hypothesis for this effect includes selective scission of protein molecules and excitation of surrounding water molecules, with the scission process currently favored. In this article, we describe the postablation infrared spectral decay kinetics in a model collagen-like peptide (Pro-Pro-Gly)(10).

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In this paper we present chemically highly resolved images obtained with Scanning Near-field Optical Microscopy (SNOM) coupled with an Infrared (IR) Free Electron Laser (FEL) at Vanderbilt University, Nashville, USA. Main principles governing SNOM imaging as well as essential components of the experimental setup are described. Chemically resolved images showing the distribution of different phases within the boron-nitride films are presented.

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The infrared (IR) absorption of a biological system can potentially report on fundamentally important microchemical properties. For example, molecular IR profiles are known to change during increases in metabolic flux, protein phosphorylation, or proteolytic cleavage. However, practical implementation of intracellular IR imaging has been problematic because the diffraction limit of conventional infrared microscopy results in low spatial resolution.

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Light scattering is used to monitor the dynamics and energy thresholds of laser-induced structural alterations in biopolymers due to irradiation by a free electron laser (FEL) in the infrared (IR) wavelength range 2.2 to 8.5 microm.

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