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Title: The effect of varying Co layer thickness on the time-temperature characteristics of Co/Sb semimetal embedded magnetic nanoparticles

Abstract

We report the effect of varying cobalt thickness on the temperature-dependent time decay of the electrical resistance of Co/Sb multilayer samples. We find that for a given temperature, a five fold change in the Co thickness produces a 100 fold change in the characteristic decay time of the resistance. We find that the characteristic decay time, as a function of temperature, follows an Arrhenius law. During deposition, the Co evolves single domain magnetic nanoparticles, on the Sb, in either a Volmer-Weber or Stranski-Krastanov growth mode. This metastable state is then encased in 2.5 nm of Sb producing an embedded nanoparticle system. Scanning tunneling microscopy measurements taken before sample aging (annealing at a given temperature for enough time to complete the resistance decay) and after aging show that these nanoparticles undergo morphological transformations during aging. These transformations lead to well defined time dependent decays in both the magnetization and the electrical resistance, making this material an excellent candidate for an electronic time-temperature sensor.

Authors:
; ; ; ; ; ;  [1]
  1. Department of Physics, Indiana University of Pennsylvania, Indiana, Pennsylvania 15705-1098 (United States)
Publication Date:
OSTI Identifier:
22399257
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 10; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 77 NANOSCIENCE AND NANOTECHNOLOGY; AGING; ANNEALING; ANTIMONY; COBALT; DEPOSITION; ELECTRIC CONDUCTIVITY; INTERFACES; LAYERS; MAGNETIZATION; METASTABLE STATES; NANOPARTICLES; PHASE TRANSFORMATIONS; SCANNING TUNNELING MICROSCOPY; TEMPERATURE DEPENDENCE; THICKNESS; TIME DEPENDENCE

Citation Formats

Madden, M. R., Alshammary, T., Grove, B., Phillips, J., Reaz, K., Hensley, S., and Kenning, G. G. The effect of varying Co layer thickness on the time-temperature characteristics of Co/Sb semimetal embedded magnetic nanoparticles. United States: N. p., 2015. Web. doi:10.1063/1.4914543.
Madden, M. R., Alshammary, T., Grove, B., Phillips, J., Reaz, K., Hensley, S., & Kenning, G. G. The effect of varying Co layer thickness on the time-temperature characteristics of Co/Sb semimetal embedded magnetic nanoparticles. United States. doi:10.1063/1.4914543.
Madden, M. R., Alshammary, T., Grove, B., Phillips, J., Reaz, K., Hensley, S., and Kenning, G. G. Sat . "The effect of varying Co layer thickness on the time-temperature characteristics of Co/Sb semimetal embedded magnetic nanoparticles". United States. doi:10.1063/1.4914543.
@article{osti_22399257,
title = {The effect of varying Co layer thickness on the time-temperature characteristics of Co/Sb semimetal embedded magnetic nanoparticles},
author = {Madden, M. R. and Alshammary, T. and Grove, B. and Phillips, J. and Reaz, K. and Hensley, S. and Kenning, G. G.},
abstractNote = {We report the effect of varying cobalt thickness on the temperature-dependent time decay of the electrical resistance of Co/Sb multilayer samples. We find that for a given temperature, a five fold change in the Co thickness produces a 100 fold change in the characteristic decay time of the resistance. We find that the characteristic decay time, as a function of temperature, follows an Arrhenius law. During deposition, the Co evolves single domain magnetic nanoparticles, on the Sb, in either a Volmer-Weber or Stranski-Krastanov growth mode. This metastable state is then encased in 2.5 nm of Sb producing an embedded nanoparticle system. Scanning tunneling microscopy measurements taken before sample aging (annealing at a given temperature for enough time to complete the resistance decay) and after aging show that these nanoparticles undergo morphological transformations during aging. These transformations lead to well defined time dependent decays in both the magnetization and the electrical resistance, making this material an excellent candidate for an electronic time-temperature sensor.},
doi = {10.1063/1.4914543},
journal = {Journal of Applied Physics},
number = 10,
volume = 117,
place = {United States},
year = {Sat Mar 14 00:00:00 EDT 2015},
month = {Sat Mar 14 00:00:00 EDT 2015}
}
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