Energetic Distribution of States in Irradiated Low-Density Polyethylene from UV-Vis-NIR Spectroscopy

ORAL

Abstract

Optical spectroscopy has been used to characterize the energetic density of states of low-density polyethylene (LDPE) and determine its optical band gap, E$_{\mathrm{g}}$, and Urbach Energy, E$_{\mathrm{U}}$ (a measure of the width of the energetic distribution of localized states within the mobility gap of disordered materials). LDPE is a prototypical highly disordered insulating material; its properties are of practical interest due to its myriad of applications from spacecraft charging to high voltage DC power cable insulation, where it can be susceptible to ionizing and UV radiation. To determine the effects of radiation on the density of states, UV-Vis-NIR transmittance spectra (200-2500 nm wavelength) were measured for pristine and irradiated samples. Total ionizing doses of 1 MGy and 4 MGy from a monoenergetic 100 keV electron beam were studied. To more accurately determine the absorption coefficient (and therefore E$_{\mathrm{U}})$, the reflectance is also required. Reflectance and transmittance were measured for pristine LDPE and these data were then used to scale the measurements of the irradiated samples. Comparison with other methods to determine the energy density of states of LDPE are discussed.

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Authors

  • Zachary Gibson

    Utah State University

  • Barry Ritchie

    University of New Mexico, Ion Linac Systems, Tech-X Corporation, Los Alamos National Laboratory, Ronald Reagan UCLA Medical Center, Brigham Young University, Brigham Young University - Provo, United States Air Force Academy, university of Michigan, SISSA, Trieste, Stanford University, Worcester Polytechnic Institute, Grinnell College, Department of Physics, Arizona State University, Brookhaven National Laboratory, University of Southern California, Argonne National Laboratory, Department of Electrical and Computer Engineering, University of New Mexico, Department of Electrical and Computer Engineering and Department of Mechanical Engineering, University of New Mexico, Lock Haven University, Illinois State University, Department of Physics, Utah State University, Logan, Utah, 84322, Department of Physics, New Mexico State University, Las Cruces, New Mexico 88003, USA, Department of Materials, Devices, and Energy Technologies, Sandia National Laboratories, Albuquerque, New Mexico 87185, USA, Kyoto University, University of Guadalajara, University of Florida, Embry-Riddle Aeronautical University, Air Force Research Laboratory, Space Vehicles Directorate, Assurance Technology Corporation, Carlisle, MA, Georgia Tech Research Institute, Atlanta, GA, Utah State University, Georgia Institute of Technology, University of Tennessee, Knoxville, Arizona State University, Department of Physics, United States Air Force Academy, 80840 USAFA, CO, USA, Shaffer Consulting Inc, Max Planck Institute for Astrophysics, Harvard University, Max Planck Institute for Gravitational Physics, Albert Einstein Institute, ASU

  • Barry Ritchie

    University of New Mexico, Ion Linac Systems, Tech-X Corporation, Los Alamos National Laboratory, Ronald Reagan UCLA Medical Center, Brigham Young University, Brigham Young University - Provo, United States Air Force Academy, university of Michigan, SISSA, Trieste, Stanford University, Worcester Polytechnic Institute, Grinnell College, Department of Physics, Arizona State University, Brookhaven National Laboratory, University of Southern California, Argonne National Laboratory, Department of Electrical and Computer Engineering, University of New Mexico, Department of Electrical and Computer Engineering and Department of Mechanical Engineering, University of New Mexico, Lock Haven University, Illinois State University, Department of Physics, Utah State University, Logan, Utah, 84322, Department of Physics, New Mexico State University, Las Cruces, New Mexico 88003, USA, Department of Materials, Devices, and Energy Technologies, Sandia National Laboratories, Albuquerque, New Mexico 87185, USA, Kyoto University, University of Guadalajara, University of Florida, Embry-Riddle Aeronautical University, Air Force Research Laboratory, Space Vehicles Directorate, Assurance Technology Corporation, Carlisle, MA, Georgia Tech Research Institute, Atlanta, GA, Utah State University, Georgia Institute of Technology, University of Tennessee, Knoxville, Arizona State University, Department of Physics, United States Air Force Academy, 80840 USAFA, CO, USA, Shaffer Consulting Inc, Max Planck Institute for Astrophysics, Harvard University, Max Planck Institute for Gravitational Physics, Albert Einstein Institute, ASU

  • Barry Ritchie

    University of New Mexico, Ion Linac Systems, Tech-X Corporation, Los Alamos National Laboratory, Ronald Reagan UCLA Medical Center, Brigham Young University, Brigham Young University - Provo, United States Air Force Academy, university of Michigan, SISSA, Trieste, Stanford University, Worcester Polytechnic Institute, Grinnell College, Department of Physics, Arizona State University, Brookhaven National Laboratory, University of Southern California, Argonne National Laboratory, Department of Electrical and Computer Engineering, University of New Mexico, Department of Electrical and Computer Engineering and Department of Mechanical Engineering, University of New Mexico, Lock Haven University, Illinois State University, Department of Physics, Utah State University, Logan, Utah, 84322, Department of Physics, New Mexico State University, Las Cruces, New Mexico 88003, USA, Department of Materials, Devices, and Energy Technologies, Sandia National Laboratories, Albuquerque, New Mexico 87185, USA, Kyoto University, University of Guadalajara, University of Florida, Embry-Riddle Aeronautical University, Air Force Research Laboratory, Space Vehicles Directorate, Assurance Technology Corporation, Carlisle, MA, Georgia Tech Research Institute, Atlanta, GA, Utah State University, Georgia Institute of Technology, University of Tennessee, Knoxville, Arizona State University, Department of Physics, United States Air Force Academy, 80840 USAFA, CO, USA, Shaffer Consulting Inc, Max Planck Institute for Astrophysics, Harvard University, Max Planck Institute for Gravitational Physics, Albert Einstein Institute, ASU

  • Barry Ritchie

    University of New Mexico, Ion Linac Systems, Tech-X Corporation, Los Alamos National Laboratory, Ronald Reagan UCLA Medical Center, Brigham Young University, Brigham Young University - Provo, United States Air Force Academy, university of Michigan, SISSA, Trieste, Stanford University, Worcester Polytechnic Institute, Grinnell College, Department of Physics, Arizona State University, Brookhaven National Laboratory, University of Southern California, Argonne National Laboratory, Department of Electrical and Computer Engineering, University of New Mexico, Department of Electrical and Computer Engineering and Department of Mechanical Engineering, University of New Mexico, Lock Haven University, Illinois State University, Department of Physics, Utah State University, Logan, Utah, 84322, Department of Physics, New Mexico State University, Las Cruces, New Mexico 88003, USA, Department of Materials, Devices, and Energy Technologies, Sandia National Laboratories, Albuquerque, New Mexico 87185, USA, Kyoto University, University of Guadalajara, University of Florida, Embry-Riddle Aeronautical University, Air Force Research Laboratory, Space Vehicles Directorate, Assurance Technology Corporation, Carlisle, MA, Georgia Tech Research Institute, Atlanta, GA, Utah State University, Georgia Institute of Technology, University of Tennessee, Knoxville, Arizona State University, Department of Physics, United States Air Force Academy, 80840 USAFA, CO, USA, Shaffer Consulting Inc, Max Planck Institute for Astrophysics, Harvard University, Max Planck Institute for Gravitational Physics, Albert Einstein Institute, ASU

  • Barry Ritchie

    University of New Mexico, Ion Linac Systems, Tech-X Corporation, Los Alamos National Laboratory, Ronald Reagan UCLA Medical Center, Brigham Young University, Brigham Young University - Provo, United States Air Force Academy, university of Michigan, SISSA, Trieste, Stanford University, Worcester Polytechnic Institute, Grinnell College, Department of Physics, Arizona State University, Brookhaven National Laboratory, University of Southern California, Argonne National Laboratory, Department of Electrical and Computer Engineering, University of New Mexico, Department of Electrical and Computer Engineering and Department of Mechanical Engineering, University of New Mexico, Lock Haven University, Illinois State University, Department of Physics, Utah State University, Logan, Utah, 84322, Department of Physics, New Mexico State University, Las Cruces, New Mexico 88003, USA, Department of Materials, Devices, and Energy Technologies, Sandia National Laboratories, Albuquerque, New Mexico 87185, USA, Kyoto University, University of Guadalajara, University of Florida, Embry-Riddle Aeronautical University, Air Force Research Laboratory, Space Vehicles Directorate, Assurance Technology Corporation, Carlisle, MA, Georgia Tech Research Institute, Atlanta, GA, Utah State University, Georgia Institute of Technology, University of Tennessee, Knoxville, Arizona State University, Department of Physics, United States Air Force Academy, 80840 USAFA, CO, USA, Shaffer Consulting Inc, Max Planck Institute for Astrophysics, Harvard University, Max Planck Institute for Gravitational Physics, Albert Einstein Institute, ASU