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Title: Room-temperature ferromagnetism in Cr-doped Si achieved by controlling atomic structure, Cr concentration, and carrier densities: A first-principles study

Abstract

By using first-principles calculations, we investigated how to achieve a strong ferromagnetism in Cr-doped Si by controlling the atomic structure and Cr concentration as well as carrier densities. We found that the configuration in which the Cr atom occupies the tetrahedral interstitial site can exist stably and the Cr atom has a large magnetic moment. Using this doping configuration, room-temperature ferromagnetism can be achieved in both n-type and p-type Si by tuning Cr concentration and carrier densities. The results indicate that the carrier density plays a crucial role in realizing strong ferromagnetism in diluted magnetic semiconductors.

Authors:
;  [1];  [2];  [3];  [4];  [5]
  1. State Key Laboratory of Surface Physics, Key Laboratory for Computational Physical Sciences (MOE), and Department of Physics, Fudan University, Shanghai 200433 (China)
  2. College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 211100 (China)
  3. Department of Physics and Electronic Engineering, Hanshan Normal University, Chaozhou 521041 (China)
  4. (China)
  5. (Korea, Republic of)
Publication Date:
OSTI Identifier:
22402923
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 16; Other Information: (c) 2015 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; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATOMS; CARRIER DENSITY; CHROMIUM; CONCENTRATION RATIO; DOPED MATERIALS; ELECTRONIC STRUCTURE; FERROMAGNETISM; MAGNETIC MOMENTS; MAGNETIC SEMICONDUCTORS; N-TYPE CONDUCTORS; P-TYPE CONDUCTORS; SILICON; TEMPERATURE RANGE 0273-0400 K

Citation Formats

Wei, Xin-Yuan, Yang, Zhong-Qin, Zhu, Yan, Li, Yun, E-mail: yun.li141@gmail.com, State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, and Department of Physics and Astronomy, Center for Strongly Correlated Materials Research, Seoul National University, Seoul 151-747. Room-temperature ferromagnetism in Cr-doped Si achieved by controlling atomic structure, Cr concentration, and carrier densities: A first-principles study. United States: N. p., 2015. Web. doi:10.1063/1.4919430.
Wei, Xin-Yuan, Yang, Zhong-Qin, Zhu, Yan, Li, Yun, E-mail: yun.li141@gmail.com, State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, & Department of Physics and Astronomy, Center for Strongly Correlated Materials Research, Seoul National University, Seoul 151-747. Room-temperature ferromagnetism in Cr-doped Si achieved by controlling atomic structure, Cr concentration, and carrier densities: A first-principles study. United States. doi:10.1063/1.4919430.
Wei, Xin-Yuan, Yang, Zhong-Qin, Zhu, Yan, Li, Yun, E-mail: yun.li141@gmail.com, State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, and Department of Physics and Astronomy, Center for Strongly Correlated Materials Research, Seoul National University, Seoul 151-747. Tue . "Room-temperature ferromagnetism in Cr-doped Si achieved by controlling atomic structure, Cr concentration, and carrier densities: A first-principles study". United States. doi:10.1063/1.4919430.
@article{osti_22402923,
title = {Room-temperature ferromagnetism in Cr-doped Si achieved by controlling atomic structure, Cr concentration, and carrier densities: A first-principles study},
author = {Wei, Xin-Yuan and Yang, Zhong-Qin and Zhu, Yan and Li, Yun, E-mail: yun.li141@gmail.com and State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433 and Department of Physics and Astronomy, Center for Strongly Correlated Materials Research, Seoul National University, Seoul 151-747},
abstractNote = {By using first-principles calculations, we investigated how to achieve a strong ferromagnetism in Cr-doped Si by controlling the atomic structure and Cr concentration as well as carrier densities. We found that the configuration in which the Cr atom occupies the tetrahedral interstitial site can exist stably and the Cr atom has a large magnetic moment. Using this doping configuration, room-temperature ferromagnetism can be achieved in both n-type and p-type Si by tuning Cr concentration and carrier densities. The results indicate that the carrier density plays a crucial role in realizing strong ferromagnetism in diluted magnetic semiconductors.},
doi = {10.1063/1.4919430},
journal = {Journal of Applied Physics},
number = 16,
volume = 117,
place = {United States},
year = {Tue Apr 28 00:00:00 EDT 2015},
month = {Tue Apr 28 00:00:00 EDT 2015}
}
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