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Title: Magnetism of gold nanorods probed using electron spin resonance

Abstract

Electron spin resonance (ESR) spectroscopy has been performed for gold nanorods (AuNRs) of four different sizes covered with a diamagnetic stabilizing component, cetyltrimethylammonium bromide. ESR signals were detected in AuNRs except the largest one. Two smallest AuNRs showed an abrupt change in the temperature dependence of resonance field and line width at around 60 K, indicating ferromagnetic phase transition. In medium-size AuNRs, the resonance with a large shift was observed below 100 K. The resonance field shifts at the lowest temperature exhibit systematic variation with the system size, which is explained by considering magnetic anisotropy for the ferromagnetic resonance.

Authors:
;  [1]; ;  [2]; ;  [3]
  1. Department of Applied Quantum Physics, Kyushu University, Fukuoka 819-0395 (Japan)
  2. Department of Applied Chemistry, Kyushu University, Fukuoka 819-0395 (Japan)
  3. Department of Material Physics and Chemistry, Faculty of Engineering, Kyushu University, Fukuoka 819-0395 (Japan)
Publication Date:
OSTI Identifier:
22590550
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANISOTROPY; ELECTRON SPIN RESONANCE; FERROMAGNETIC RESONANCE; GOLD; LINE WIDTHS; MAGNETISM; NANOSTRUCTURES; PHASE TRANSFORMATIONS; PROBES; SIGNALS; SPECTROSCOPY; TEMPERATURE DEPENDENCE

Citation Formats

Inagaki, Y., E-mail: inagaki.yuji.318@m.kyushu-u.ac.jp, Kawae, T., Yonemura, H., Yamada, S., Sakai, N., and Makihara, Y.. Magnetism of gold nanorods probed using electron spin resonance. United States: N. p., 2016. Web. doi:10.1063/1.4961369.
Inagaki, Y., E-mail: inagaki.yuji.318@m.kyushu-u.ac.jp, Kawae, T., Yonemura, H., Yamada, S., Sakai, N., & Makihara, Y.. Magnetism of gold nanorods probed using electron spin resonance. United States. doi:10.1063/1.4961369.
Inagaki, Y., E-mail: inagaki.yuji.318@m.kyushu-u.ac.jp, Kawae, T., Yonemura, H., Yamada, S., Sakai, N., and Makihara, Y.. 2016. "Magnetism of gold nanorods probed using electron spin resonance". United States. doi:10.1063/1.4961369.
@article{osti_22590550,
title = {Magnetism of gold nanorods probed using electron spin resonance},
author = {Inagaki, Y., E-mail: inagaki.yuji.318@m.kyushu-u.ac.jp and Kawae, T. and Yonemura, H. and Yamada, S. and Sakai, N. and Makihara, Y.},
abstractNote = {Electron spin resonance (ESR) spectroscopy has been performed for gold nanorods (AuNRs) of four different sizes covered with a diamagnetic stabilizing component, cetyltrimethylammonium bromide. ESR signals were detected in AuNRs except the largest one. Two smallest AuNRs showed an abrupt change in the temperature dependence of resonance field and line width at around 60 K, indicating ferromagnetic phase transition. In medium-size AuNRs, the resonance with a large shift was observed below 100 K. The resonance field shifts at the lowest temperature exhibit systematic variation with the system size, which is explained by considering magnetic anisotropy for the ferromagnetic resonance.},
doi = {10.1063/1.4961369},
journal = {Applied Physics Letters},
number = 7,
volume = 109,
place = {United States},
year = 2016,
month = 8
}
  • Electron energy-loss spectroscopy and energy-filtered transmission electron-microscope imaging are used to characterize the energy distribution of the surface plasmon of isolated and coupled gold nanorods. Local-field enhancement and spectral shift of the plasmon modes are observed for two interacting nanoparticles. The spatial modes measured by energy loss are shown to share qualitative similarities with the electromagnetic field distribution around gold nanorods induced by optical excitation as simulated using the discrete dipole-approximation method.
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