Intergranular tunneling magnetoresistance of mechanically alloyed (Cr-M)O2 powder compacts

M. Tsunoda; Tsugio Sato; Kibu Chiyo; B. Jeyadevan; Migaku Takahashi

doi:10.1109/TMAG.2005.855213

Intergranular tunneling magnetoresistance of mechanically alloyed (Cr-M)O₂ powder compacts

M. Tsunoda, Tsugio Sato, Kibu Chiyo, B. Jeyadevan, Migaku Takahashi

ENG - Electronic Engineering

Research output: Contribution to journal › Article › peer-review

1 Citation (Scopus)

Abstract

The (Cr-M)O₂ (M = V, Mn, Fe, Co) powders were synthesized by the mechanochemical method and the magnetoresistance (MR) effect of their powder compacts was investigated as a function of the type and content of the dopant. The findings are summarized as follows. 1) Substituting limit of M for Cr in CrO₂ was 30 at% for V, Mn, and Co, and 5 at% for Fe. 2) Doping with V effectively decreases the TC, while Fe significantly elevates the same (420 K with 5 at% Fe). Furthermore, the changes observed in the cases of Co and Mn was marginal. 3) MR ratio was significantly enhanced with the doping of 5 at % of Fe, however, decreased in the cases of V and Co doping. 4) The reason for the MR enhancement in (Cr-Fe)O₂ powder compacts is due to the change in the barrier characteristics.

Original language	English
Pages (from-to)	3400-3402
Number of pages	3
Journal	IEEE Transactions on Magnetics
Volume	41
Issue number	10
DOIs	https://doi.org/10.1109/TMAG.2005.855213
Publication status	Published - 2005 Oct

Keywords

Chromium dioxide
Half metal
Intergranular tunneling
Magnetoresistance
Tunnel barrier

ASJC Scopus subject areas

Electronic, Optical and Magnetic Materials
Electrical and Electronic Engineering

Access to Document

10.1109/TMAG.2005.855213

Cite this

@article{2bd859e9d6af4bd4b01960d798442430,

title = "Intergranular tunneling magnetoresistance of mechanically alloyed (Cr-M)O2 powder compacts",

abstract = "The (Cr-M)O2 (M = V, Mn, Fe, Co) powders were synthesized by the mechanochemical method and the magnetoresistance (MR) effect of their powder compacts was investigated as a function of the type and content of the dopant. The findings are summarized as follows. 1) Substituting limit of M for Cr in CrO2 was 30 at% for V, Mn, and Co, and 5 at% for Fe. 2) Doping with V effectively decreases the TC, while Fe significantly elevates the same (420 K with 5 at% Fe). Furthermore, the changes observed in the cases of Co and Mn was marginal. 3) MR ratio was significantly enhanced with the doping of 5 at % of Fe, however, decreased in the cases of V and Co doping. 4) The reason for the MR enhancement in (Cr-Fe)O2 powder compacts is due to the change in the barrier characteristics.",

keywords = "Chromium dioxide, Half metal, Intergranular tunneling, Magnetoresistance, Tunnel barrier",

author = "M. Tsunoda and Tsugio Sato and Kibu Chiyo and B. Jeyadevan and Migaku Takahashi",

note = "Funding Information: This research was supported in part by the Ministry of Education, Science, Sports and Culture, Grant-in-Aid for Scientific Research (B), 163 602 00, 2004.",

year = "2005",

month = oct,

doi = "10.1109/TMAG.2005.855213",

language = "English",

volume = "41",

pages = "3400--3402",

journal = "IEEE Transactions on Magnetics",

issn = "0018-9464",

publisher = "Institute of Electrical and Electronics Engineers Inc.",

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TY - JOUR

T1 - Intergranular tunneling magnetoresistance of mechanically alloyed (Cr-M)O2 powder compacts

AU - Tsunoda, M.

AU - Sato, Tsugio

AU - Chiyo, Kibu

AU - Jeyadevan, B.

AU - Takahashi, Migaku

N1 - Funding Information: This research was supported in part by the Ministry of Education, Science, Sports and Culture, Grant-in-Aid for Scientific Research (B), 163 602 00, 2004.

PY - 2005/10

Y1 - 2005/10

N2 - The (Cr-M)O2 (M = V, Mn, Fe, Co) powders were synthesized by the mechanochemical method and the magnetoresistance (MR) effect of their powder compacts was investigated as a function of the type and content of the dopant. The findings are summarized as follows. 1) Substituting limit of M for Cr in CrO2 was 30 at% for V, Mn, and Co, and 5 at% for Fe. 2) Doping with V effectively decreases the TC, while Fe significantly elevates the same (420 K with 5 at% Fe). Furthermore, the changes observed in the cases of Co and Mn was marginal. 3) MR ratio was significantly enhanced with the doping of 5 at % of Fe, however, decreased in the cases of V and Co doping. 4) The reason for the MR enhancement in (Cr-Fe)O2 powder compacts is due to the change in the barrier characteristics.

AB - The (Cr-M)O2 (M = V, Mn, Fe, Co) powders were synthesized by the mechanochemical method and the magnetoresistance (MR) effect of their powder compacts was investigated as a function of the type and content of the dopant. The findings are summarized as follows. 1) Substituting limit of M for Cr in CrO2 was 30 at% for V, Mn, and Co, and 5 at% for Fe. 2) Doping with V effectively decreases the TC, while Fe significantly elevates the same (420 K with 5 at% Fe). Furthermore, the changes observed in the cases of Co and Mn was marginal. 3) MR ratio was significantly enhanced with the doping of 5 at % of Fe, however, decreased in the cases of V and Co doping. 4) The reason for the MR enhancement in (Cr-Fe)O2 powder compacts is due to the change in the barrier characteristics.

KW - Chromium dioxide

KW - Half metal

KW - Intergranular tunneling

KW - Magnetoresistance

KW - Tunnel barrier

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