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Title: Ferromagnetic-phase transition in the spinel-type CuCr{sub 2}Te{sub 4}

Abstract

Ferromagnetic-phase transition in spinel-type CuCr{sub 2}Te{sub 4} has been clearly observed. CuCr{sub 2}Te{sub 4} is a telluride-spinel with the lattice constant a=11.134A, which has been synthesized successfully. The heat capacity exhibits a sharp peak due to the ferromagnetic-phase transition with the Curie temperature T{sub C}=326K. This value of T{sub C} corresponds exactly to that of the negative peak of dM/dT in low field of 1.0Oe. The magnetic susceptibility shows the Curie-Weiss behavior between 380 and 650K with the effective magnetic moment {mu}{sub eff}=4.14{mu}{sub B}/Cr-ion and the Weiss constant {theta}=+357K. The low temperature magnetization indicates the spin-wave excitations, where the existence of first term of Bloch T{sup 3/2} law and the next T{sup 5/2} term are verified experimentally. This spin-wave excitation is detected up to approximately 250K which is a fairly high temperature.

Authors:
 [1];  [1];  [1];  [1];  [2];  [2];  [3];  [3];  [4]
  1. Department of Materials Science and Engineering, Muroran Institute of Technology, 27-1 Mizumoto-cho, Muroran, Hokkaido 050-8585 (Japan)
  2. Department of Quantum Matter, Graduate School of Advanced Science of Matter, Hiroshima University, Higashi-Hiroshima 739-8526 (Japan)
  3. Department of Physics, University of the Ryukyus, Okinawa 903-0213 (Japan)
  4. Department of Materials Science and Engineering, Muroran Institute of Technology, 27-1 Mizumoto-cho, Muroran, Hokkaido 050-8585 (Japan). E-mail: naga-sho@mmm.muroran-it.ac.jp
Publication Date:
OSTI Identifier:
20784842
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 179; Journal Issue: 1; Other Information: DOI: 10.1016/j.jssc.2005.10.007; PII: S0022-4596(05)00467-6; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CHROMIUM IONS; CHROMIUM TELLURIDES; COPPER TELLURIDES; CURIE POINT; EXCITATION; FERROMAGNETISM; LATTICE PARAMETERS; MAGNETIC MOMENTS; MAGNETIC SUSCEPTIBILITY; MAGNETIZATION; PHASE TRANSFORMATIONS; SPECIFIC HEAT; SPIN WAVES; SPINELS; TEMPERATURE RANGE 0273-0400 K; TEMPERATURE RANGE 0400-1000 K

Citation Formats

Suzuyama, Takeshi, Awaka, Junji, Yamamoto, Hiroki, Ebisu, Shuji, Ito, Masakazu, Suzuki, Takashi, Nakama, Takao, Yagasaki, Katsuma, and Nagata, Shoichi. Ferromagnetic-phase transition in the spinel-type CuCr{sub 2}Te{sub 4}. United States: N. p., 2006. Web. doi:10.1016/j.jssc.2005.10.007.
Suzuyama, Takeshi, Awaka, Junji, Yamamoto, Hiroki, Ebisu, Shuji, Ito, Masakazu, Suzuki, Takashi, Nakama, Takao, Yagasaki, Katsuma, & Nagata, Shoichi. Ferromagnetic-phase transition in the spinel-type CuCr{sub 2}Te{sub 4}. United States. doi:10.1016/j.jssc.2005.10.007.
Suzuyama, Takeshi, Awaka, Junji, Yamamoto, Hiroki, Ebisu, Shuji, Ito, Masakazu, Suzuki, Takashi, Nakama, Takao, Yagasaki, Katsuma, and Nagata, Shoichi. Sun . "Ferromagnetic-phase transition in the spinel-type CuCr{sub 2}Te{sub 4}". United States. doi:10.1016/j.jssc.2005.10.007.
@article{osti_20784842,
title = {Ferromagnetic-phase transition in the spinel-type CuCr{sub 2}Te{sub 4}},
author = {Suzuyama, Takeshi and Awaka, Junji and Yamamoto, Hiroki and Ebisu, Shuji and Ito, Masakazu and Suzuki, Takashi and Nakama, Takao and Yagasaki, Katsuma and Nagata, Shoichi},
abstractNote = {Ferromagnetic-phase transition in spinel-type CuCr{sub 2}Te{sub 4} has been clearly observed. CuCr{sub 2}Te{sub 4} is a telluride-spinel with the lattice constant a=11.134A, which has been synthesized successfully. The heat capacity exhibits a sharp peak due to the ferromagnetic-phase transition with the Curie temperature T{sub C}=326K. This value of T{sub C} corresponds exactly to that of the negative peak of dM/dT in low field of 1.0Oe. The magnetic susceptibility shows the Curie-Weiss behavior between 380 and 650K with the effective magnetic moment {mu}{sub eff}=4.14{mu}{sub B}/Cr-ion and the Weiss constant {theta}=+357K. The low temperature magnetization indicates the spin-wave excitations, where the existence of first term of Bloch T{sup 3/2} law and the next T{sup 5/2} term are verified experimentally. This spin-wave excitation is detected up to approximately 250K which is a fairly high temperature.},
doi = {10.1016/j.jssc.2005.10.007},
journal = {Journal of Solid State Chemistry},
number = 1,
volume = 179,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2006},
month = {Sun Jan 15 00:00:00 EST 2006}
}
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