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Title: Unexpected magnetization enhancement in hydrogen plasma treated ferromagnetic (Zn,Cu)O film

Abstract

The effects of H{sup +} incorporation on oxygen vacancies (H{sub O}{sup +}) on the giant ferromagnetic behavior (moment up to 3.26 μ{sub B}/Cu) in ZnO:Cu polycrystalline films have been closely examined using different microstructural and magnetic characterization tools. Fine thermal stability (up to 450 °C) and low resistivity demonstrate a significant correlation between Cu 3d-states and H{sub O}{sup +} donor defects in H plasma treated ZnO:Cu films, analogous to dual-donor (V{sub O} and Zn{sub i}) defects mediated case. These H{sub O}{sup +} donors can delocalize their electrons to the orbits of Cu atoms and contribute to a stronger spin-orbit coupling interaction. Suitable H{sub O}{sup +} defect concentration and matched proportion between Cu{sup 2+} and Cu{sup +} species ensure that orbital momentum shall not be quenched. Hence, unexpected moment enhancement, less than spin-orbit coupling upper limit (3.55 μ{sub B}/Cu), can be also expected in this scenario. The manipulation from spin-only to spin-orbit coupling mode, using a facile thermally-mediated H plasma exposure way, will allow achieving spin transport based diluted magnetic semiconductor device.

Authors:
; ; ;  [1]
  1. State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China and Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310027 (China)
Publication Date:
OSTI Identifier:
22310897
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 7; 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; COPPER ADDITIONS; COPPER IONS; COPPER OXIDES; CRYSTAL DEFECTS; FILMS; HYDROGEN IONS; L-S COUPLING; MAGNETIC SEMICONDUCTORS; MAGNETIZATION; MICROSTRUCTURE; OXYGEN IONS; PLASMA; POLYCRYSTALS; SPIN; ZINC OXIDES

Citation Formats

Hu, Liang, Zhu, Liping, E-mail: zlp1@zju.edu.cn, E-mail: hphe@zju.edu.cn, He, Haiping, E-mail: zlp1@zju.edu.cn, E-mail: hphe@zju.edu.cn, and Ye, Zhizhen. Unexpected magnetization enhancement in hydrogen plasma treated ferromagnetic (Zn,Cu)O film. United States: N. p., 2014. Web. doi:10.1063/1.4893946.
Hu, Liang, Zhu, Liping, E-mail: zlp1@zju.edu.cn, E-mail: hphe@zju.edu.cn, He, Haiping, E-mail: zlp1@zju.edu.cn, E-mail: hphe@zju.edu.cn, & Ye, Zhizhen. Unexpected magnetization enhancement in hydrogen plasma treated ferromagnetic (Zn,Cu)O film. United States. doi:10.1063/1.4893946.
Hu, Liang, Zhu, Liping, E-mail: zlp1@zju.edu.cn, E-mail: hphe@zju.edu.cn, He, Haiping, E-mail: zlp1@zju.edu.cn, E-mail: hphe@zju.edu.cn, and Ye, Zhizhen. Mon . "Unexpected magnetization enhancement in hydrogen plasma treated ferromagnetic (Zn,Cu)O film". United States. doi:10.1063/1.4893946.
@article{osti_22310897,
title = {Unexpected magnetization enhancement in hydrogen plasma treated ferromagnetic (Zn,Cu)O film},
author = {Hu, Liang and Zhu, Liping, E-mail: zlp1@zju.edu.cn, E-mail: hphe@zju.edu.cn and He, Haiping, E-mail: zlp1@zju.edu.cn, E-mail: hphe@zju.edu.cn and Ye, Zhizhen},
abstractNote = {The effects of H{sup +} incorporation on oxygen vacancies (H{sub O}{sup +}) on the giant ferromagnetic behavior (moment up to 3.26 μ{sub B}/Cu) in ZnO:Cu polycrystalline films have been closely examined using different microstructural and magnetic characterization tools. Fine thermal stability (up to 450 °C) and low resistivity demonstrate a significant correlation between Cu 3d-states and H{sub O}{sup +} donor defects in H plasma treated ZnO:Cu films, analogous to dual-donor (V{sub O} and Zn{sub i}) defects mediated case. These H{sub O}{sup +} donors can delocalize their electrons to the orbits of Cu atoms and contribute to a stronger spin-orbit coupling interaction. Suitable H{sub O}{sup +} defect concentration and matched proportion between Cu{sup 2+} and Cu{sup +} species ensure that orbital momentum shall not be quenched. Hence, unexpected moment enhancement, less than spin-orbit coupling upper limit (3.55 μ{sub B}/Cu), can be also expected in this scenario. The manipulation from spin-only to spin-orbit coupling mode, using a facile thermally-mediated H plasma exposure way, will allow achieving spin transport based diluted magnetic semiconductor device.},
doi = {10.1063/1.4893946},
journal = {Applied Physics Letters},
number = 7,
volume = 105,
place = {United States},
year = {Mon Aug 18 00:00:00 EDT 2014},
month = {Mon Aug 18 00:00:00 EDT 2014}
}
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