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Title: Visualizing dispersive features in 2D image via minimum gradient method

Abstract

Here, we developed a minimum gradient based method to track ridge features in a 2D image plot, which is a typical data representation in many momentum resolved spectroscopy experiments. Through both analytic formulation and numerical simulation, we compare this new method with existing DC (distribution curve) based and higher order derivative based analyses. We find that the new method has good noise resilience and enhanced contrast especially for weak intensity features and meanwhile preserves the quantitative local maxima information from the raw image. An algorithm is proposed to extract 1D ridge dispersion from the 2D image plot, whose quantitative application to angle-resolved photoemission spectroscopy measurements on high temperature superconductors is demonstrated.

Authors:
 [1]; ORCiD logo [2];  [1]
  1. SLAC National Accelerator Lab., Menlo Park, CA (United States); Stanford Univ., Stanford, CA (United States)
  2. Stanford Univ., Stanford, CA (United States)
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1390307
Grant/Contract Number:
AC02-76SF00515
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Review of Scientific Instruments
Additional Journal Information:
Journal Volume: 88; Journal Issue: 7; Journal ID: ISSN 0034-6748
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
97 MATHEMATICS AND COMPUTING; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

Citation Formats

He, Yu, Wang, Yan, and Shen, Zhi -Xun. Visualizing dispersive features in 2D image via minimum gradient method. United States: N. p., 2017. Web. doi:10.1063/1.4993919.
He, Yu, Wang, Yan, & Shen, Zhi -Xun. Visualizing dispersive features in 2D image via minimum gradient method. United States. doi:10.1063/1.4993919.
He, Yu, Wang, Yan, and Shen, Zhi -Xun. 2017. "Visualizing dispersive features in 2D image via minimum gradient method". United States. doi:10.1063/1.4993919.
@article{osti_1390307,
title = {Visualizing dispersive features in 2D image via minimum gradient method},
author = {He, Yu and Wang, Yan and Shen, Zhi -Xun},
abstractNote = {Here, we developed a minimum gradient based method to track ridge features in a 2D image plot, which is a typical data representation in many momentum resolved spectroscopy experiments. Through both analytic formulation and numerical simulation, we compare this new method with existing DC (distribution curve) based and higher order derivative based analyses. We find that the new method has good noise resilience and enhanced contrast especially for weak intensity features and meanwhile preserves the quantitative local maxima information from the raw image. An algorithm is proposed to extract 1D ridge dispersion from the 2D image plot, whose quantitative application to angle-resolved photoemission spectroscopy measurements on high temperature superconductors is demonstrated.},
doi = {10.1063/1.4993919},
journal = {Review of Scientific Instruments},
number = 7,
volume = 88,
place = {United States},
year = 2017,
month = 7
}

Journal Article:
Free Publicly Available Full Text
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  • An X-ray technique for the measurement of internal residual strain gradients near the continuous reinforcements of metal matrix composites has been investigated. The technique utilizes high intensity white X-ray radiation from a synchrotron radiation source to obtain energy spectra from small (10[sup [minus]3] mm[sup 3]) volumes deep within composite samples. The energy peak positions satisfy Bragg's law and allow determination of the lattice parameter. As the probe volume is translated, the peaks of the spectra shift and are used to infer lattice spacing changes and thus strains with a precision of 10[sup [minus]3] to 10[sup [minus]4] (depending on the samplemore » grain size/probe volume ratio). The viability of the technique has first been tested using a model system with 800 [mu]m Al[sub 2]O[sub 3] fibers and a commercial purity titanium matrix. For this system (which remained elastic on cooling), good agreement was observed between the measured residual radial and hoop strain gradients and those estimated from a simple elastic concentric cylinders model. The technique was then used to assess the strains near (SCS-6) silicon carbide fibers in a Ti-14Al-21Nb matrix after consolidation processing. Reasonable agreement between measured and calculated strains was seen provided the probe volume was located 50 [mu]m or more from the fiber/matrix interface. Close to the interface, the measured elastic strains were smaller than anticipated, due to relaxation of the residual stress by plasticity and radial cracking during sample cooling.« less
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