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Title: Diffusion, Clustering, and Magnetic Properties of Mn dopants on a 2x2-T4 GaN(0001) Substrate

Abstract

Based on extensive rst-principles calculations with density-functional theory (DFT), we propose a growth model of Mn on reconstructed 22-T4 GaN(0001), characterized by substitution of Ga by a Mn adatom via a surface site T4. At lower Mn concentration, Mn dopants distribute in Ga sublattice randomly forming intrinsic DMS. At higher concentration, planar ferromagnetic clusters oriented in (0001) plane are easily formed at lower temperature, but ferrimagnetic zigzag columns along the growth orientation will be formed at higher temperature. Based on these ndings, we qualitatively explain the puzzling experimental observations on TC variations, as well as the dierent magnetic natures in Ga1 xMnxN systems.

Authors:
 [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1000871
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 99; Journal Issue: 16
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DIFFUSION; MAGNETIC PROPERTIES; ORIENTATION; SUBSTRATES

Citation Formats

Hao, Shiqiang, and Zhang, Zhenyu. Diffusion, Clustering, and Magnetic Properties of Mn dopants on a 2x2-T4 GaN(0001) Substrate. United States: N. p., 2007. Web. doi:10.1103/PhysRevLett.99.166101.
Hao, Shiqiang, & Zhang, Zhenyu. Diffusion, Clustering, and Magnetic Properties of Mn dopants on a 2x2-T4 GaN(0001) Substrate. United States. doi:10.1103/PhysRevLett.99.166101.
Hao, Shiqiang, and Zhang, Zhenyu. Mon . "Diffusion, Clustering, and Magnetic Properties of Mn dopants on a 2x2-T4 GaN(0001) Substrate". United States. doi:10.1103/PhysRevLett.99.166101.
@article{osti_1000871,
title = {Diffusion, Clustering, and Magnetic Properties of Mn dopants on a 2x2-T4 GaN(0001) Substrate},
author = {Hao, Shiqiang and Zhang, Zhenyu},
abstractNote = {Based on extensive rst-principles calculations with density-functional theory (DFT), we propose a growth model of Mn on reconstructed 22-T4 GaN(0001), characterized by substitution of Ga by a Mn adatom via a surface site T4. At lower Mn concentration, Mn dopants distribute in Ga sublattice randomly forming intrinsic DMS. At higher concentration, planar ferromagnetic clusters oriented in (0001) plane are easily formed at lower temperature, but ferrimagnetic zigzag columns along the growth orientation will be formed at higher temperature. Based on these ndings, we qualitatively explain the puzzling experimental observations on TC variations, as well as the dierent magnetic natures in Ga1 xMnxN systems.},
doi = {10.1103/PhysRevLett.99.166101},
journal = {Physical Review Letters},
number = 16,
volume = 99,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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