NMR and Time-Resolved Optical Studies of Brain Imaging

ABSTRACTTime-resolved reflection and transmission measurements during heating are coupled with transmission electron microscopy (TEM) to study the crystallization of amorphous 75nm Co49Si51 films. The reflection decreases and the transmission increases upon crystallization. Optical data are converted to a measure of the fraction crystallized, χ=χ(T,t). A Kissinger analysis gives an activation energy for crystallization of 1.1 eV. TEM analysis of films crystallized in-situ show they are principally CoSi2 with a small amount of CoSi2. These results are being used for kinetic modelling of crystallization of amorphous Co-silicide films for potential use in Si mosfet and bipolar technologies.

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Time-Resolved Optical Studies of Perovskite Polycrystalline Films, Single Crystals and their Surfaces

10.29363/nanoge.nfm.2018.087 ◽

2018 ◽

Author(s):

Matthew Beard

Keyword(s):

Single Crystals ◽

Polycrystalline Films ◽

Optical Studies ◽

Time Resolved

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Femtosecond Time-Resolved Optical Studies of Photoexcited States in C60

Springer Series in Solid-State Sciences - Electronic Properties of Fullerenes ◽

10.1007/978-3-642-85049-3_49 ◽

1993 ◽

pp. 292-296 ◽

Cited By ~ 2

Author(s):

T. N. Thomas ◽

R. A. Taylor ◽

J. F. Ryan ◽

D. Mihailovic ◽

R. Zamboni

Keyword(s):

Optical Studies ◽

Time Resolved

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Time Resolved Optical Studies of InGaN Layers Grown on LGO

MRS Proceedings ◽

10.1557/proc-743-l11.6 ◽

2002 ◽

Vol 743 ◽

Author(s):

Maurice Cheung ◽

Gon Namkoong ◽

Madalina Furis ◽

Fei Chen ◽

Alexander. N. Cartwright ◽

...

Keyword(s):

Structural Quality ◽

Photoluminescence Intensity ◽

X Ray Diffraction ◽

Optical Studies ◽

Time Resolved ◽

Lattice Match ◽

Spatially Resolved ◽

Recombination Processes ◽

Time Resolved Photoluminescence ◽

Intensity Decay

ABSTRACTRadiative recombination processes in bulk InGaN grown by molecular beam epitaxy (MBE) on lithium gallate (LGO or LiGaO2) substrates were investigated using microscopic PL and time-resolved photoluminescence (TRPL). The improved structural quality resulting from a better lattice match of the LGO substrate to III-V nitride materials simplifies these investigations because well-defined composition phases can be analyzed for both homogeneous and phased separated InGaN samples. Epilayers of InGaN intentionally grown with and without indium segregation were studied. X-ray diffraction measurements showed that the homogeneous epilayer was high quality In0.208Ga0.702N and the segregated epilayer exhibited peaks corresponding to both In0.289Ga0.711N and In0.443Ga0.557N indicating the presence of higher In concentration regions in this sample. Spatially resolved photoluminescence spectra confirm the existence of these regions. The photoluminescence intensity decay is non-exponential for both samples and a stretched exponential fit to the decay data confirms the existence of local potential fluctuations in which carriers are localized before recombination.

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TIME-RESOLVED OPTICAL STUDIES OF PHOTO-EXCITED STATES IN C60

International Journal of Modern Physics B ◽

10.1142/s0217979292002024 ◽

1992 ◽

Vol 06 (23n24) ◽

pp. 3931-3934 ◽

Cited By ~ 8

Author(s):

T.N. Thomas ◽

J.F. Ryan ◽

R.A. Taylor ◽

D. Mihailovič ◽

R. Zamboni

Keyword(s):

Optical Absorption ◽

Excited States ◽

Characteristic Time ◽

Laser Intensity ◽

Excitation Density ◽

Optical Studies ◽

Time Resolved

We have measured the relaxation of photo-excited states in C 60 by time-resolved optical absorption. An ultrafast response (~1ps) is observed which is found to be dependent on excitation density, the characteristic time decreasing with increasing laser intensity. This is consistent with a distortion of the molecule induced by the photo-excited electrons.

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