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Title: X-ray induced demagnetization of single-molecule magnets

Abstract

Low-temperature x-ray magnetic circular dichroism measurements on the endohedral single-molecule magnet DySc{sub 2}N@C{sub 80} at the Dy M{sub 4,5} edges reveal a shrinking of the opening of the observed hysteresis with increasing x-ray flux. Time-dependent measurements show that the exposure of the molecules to x-rays resonant with the Dy M{sub 5} edge accelerates the relaxation of magnetization more than off-resonant x-rays. The results cannot be explained by a homogeneous temperature rise due to x-ray absorption. Moreover, the observed large demagnetization cross sections indicate that the resonant absorption of one x-ray photon induces the demagnetization of many molecules.

Authors:
 [1];  [2];  [1];  [2];  [3]; ;  [1]; ;  [4];  [5]; ;  [6];  [7]
  1. Swiss Light Source, Paul Scherrer Institute, 5232 Villigen PSI (Switzerland)
  2. (Switzerland)
  3. (Sweden)
  4. Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne (Switzerland)
  5. Hefei National Laboratory for Physical Sciences at Microscale, Department of Materials Science and Engineering, University of Science and Technology of China, 96 Jinzhai Road, Hefei 230026 (China)
  6. Department of Electrochemistry and Conducting Polymers, Leibniz Institute of Solid State and Materials Research, 01069 Dresden (Germany)
  7. Physik-Institut, Universität Zürich, 8057 Zürich (Switzerland)
Publication Date:
OSTI Identifier:
22311151
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 3; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABSORPTION; CARBON; CROSS SECTIONS; DEMAGNETIZATION; DYSPROSIUM COMPOUNDS; MAGNETIC CIRCULAR DICHROISM; MAGNETIZATION; MAGNETS; MOLECULES; NITROGEN COMPOUNDS; PHOTONS; RELAXATION; RESONANCE; SCANDIUM COMPOUNDS; TIME DEPENDENCE; X RADIATION

Citation Formats

Dreiser, Jan, E-mail: jan.dreiser@epfl.ch, Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Westerström, Rasmus, Physik-Institut, Universität Zürich, 8057 Zürich, Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Piamonteze, Cinthia, Nolting, Frithjof, Rusponi, Stefano, Brune, Harald, Yang, Shangfeng, Popov, Alexey, Dunsch, Lothar, and Greber, Thomas, E-mail: greber@physik.uzh.ch. X-ray induced demagnetization of single-molecule magnets. United States: N. p., 2014. Web. doi:10.1063/1.4891485.
Dreiser, Jan, E-mail: jan.dreiser@epfl.ch, Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Westerström, Rasmus, Physik-Institut, Universität Zürich, 8057 Zürich, Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Piamonteze, Cinthia, Nolting, Frithjof, Rusponi, Stefano, Brune, Harald, Yang, Shangfeng, Popov, Alexey, Dunsch, Lothar, & Greber, Thomas, E-mail: greber@physik.uzh.ch. X-ray induced demagnetization of single-molecule magnets. United States. doi:10.1063/1.4891485.
Dreiser, Jan, E-mail: jan.dreiser@epfl.ch, Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Westerström, Rasmus, Physik-Institut, Universität Zürich, 8057 Zürich, Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Piamonteze, Cinthia, Nolting, Frithjof, Rusponi, Stefano, Brune, Harald, Yang, Shangfeng, Popov, Alexey, Dunsch, Lothar, and Greber, Thomas, E-mail: greber@physik.uzh.ch. Mon . "X-ray induced demagnetization of single-molecule magnets". United States. doi:10.1063/1.4891485.
@article{osti_22311151,
title = {X-ray induced demagnetization of single-molecule magnets},
author = {Dreiser, Jan, E-mail: jan.dreiser@epfl.ch and Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne and Westerström, Rasmus and Physik-Institut, Universität Zürich, 8057 Zürich and Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala and Piamonteze, Cinthia and Nolting, Frithjof and Rusponi, Stefano and Brune, Harald and Yang, Shangfeng and Popov, Alexey and Dunsch, Lothar and Greber, Thomas, E-mail: greber@physik.uzh.ch},
abstractNote = {Low-temperature x-ray magnetic circular dichroism measurements on the endohedral single-molecule magnet DySc{sub 2}N@C{sub 80} at the Dy M{sub 4,5} edges reveal a shrinking of the opening of the observed hysteresis with increasing x-ray flux. Time-dependent measurements show that the exposure of the molecules to x-rays resonant with the Dy M{sub 5} edge accelerates the relaxation of magnetization more than off-resonant x-rays. The results cannot be explained by a homogeneous temperature rise due to x-ray absorption. Moreover, the observed large demagnetization cross sections indicate that the resonant absorption of one x-ray photon induces the demagnetization of many molecules.},
doi = {10.1063/1.4891485},
journal = {Applied Physics Letters},
number = 3,
volume = 105,
place = {United States},
year = {Mon Jul 21 00:00:00 EDT 2014},
month = {Mon Jul 21 00:00:00 EDT 2014}
}
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