Precise tuning of the Curie temperature of (Ga,Mn)As-based magnetic semiconductors by hole compensation: Support for valence-band ferromagnetism
For the prototype diluted ferromagnetic semiconductor (Ga,Mn)As, there is a fundamental concern about the electronic states near the Fermi level, i.e., whether the Fermi level resides in a well-separated impurity band derived from Mn doping (impurity-band model) or in the valence band that is alread...
| Main Authors: | , , , , , , , , , , , , , |
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| Format: | Article |
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American Physical Society
2016
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| Online Access: | https://eprints.nottingham.ac.uk/37051/ |
| _version_ | 1848795382540140544 |
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| author | Zhou, Shengqiang Li, Lin Yuan, Ye Rushforth, A.W. Chen, Lin Wang, Yutian Böttger, R. Heller, R. Zhao, Jianhua Edmonds, K.W. Campion, R.P. Gallagher, B.L. Timm, C. Helm, M. |
| author_facet | Zhou, Shengqiang Li, Lin Yuan, Ye Rushforth, A.W. Chen, Lin Wang, Yutian Böttger, R. Heller, R. Zhao, Jianhua Edmonds, K.W. Campion, R.P. Gallagher, B.L. Timm, C. Helm, M. |
| author_sort | Zhou, Shengqiang |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | For the prototype diluted ferromagnetic semiconductor (Ga,Mn)As, there is a fundamental concern about the electronic states near the Fermi level, i.e., whether the Fermi level resides in a well-separated impurity band derived from Mn doping (impurity-band model) or in the valence band that is already merged with the Mn-derived impurity band (valence-band model). We investigate this question by carefully shifting the Fermi level by means of carrier compensation. We use helium-ion implantation, a standard industry technology, to precisely compensate the hole doping of GaAs-based diluted ferromagnetic semiconductors while keeping the Mn concentration constant. We monitor the change of Curie temperature (TC) and conductivity. For a broad range of samples including (Ga,Mn)As and (Ga,Mn)(As,P) with various Mn and P concentrations, we observe a smooth decrease of TC with carrier compensation over a wide temperature range while the conduction is changed from metallic to insulating. The existence of TC below 10 K is also confirmed in heavily compensated samples. Our experimental results are naturally explained within the valence-band picture. |
| first_indexed | 2025-11-14T19:31:12Z |
| format | Article |
| id | nottingham-37051 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| last_indexed | 2025-11-14T19:31:12Z |
| publishDate | 2016 |
| publisher | American Physical Society |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-370512020-05-04T18:07:02Z https://eprints.nottingham.ac.uk/37051/ Precise tuning of the Curie temperature of (Ga,Mn)As-based magnetic semiconductors by hole compensation: Support for valence-band ferromagnetism Zhou, Shengqiang Li, Lin Yuan, Ye Rushforth, A.W. Chen, Lin Wang, Yutian Böttger, R. Heller, R. Zhao, Jianhua Edmonds, K.W. Campion, R.P. Gallagher, B.L. Timm, C. Helm, M. For the prototype diluted ferromagnetic semiconductor (Ga,Mn)As, there is a fundamental concern about the electronic states near the Fermi level, i.e., whether the Fermi level resides in a well-separated impurity band derived from Mn doping (impurity-band model) or in the valence band that is already merged with the Mn-derived impurity band (valence-band model). We investigate this question by carefully shifting the Fermi level by means of carrier compensation. We use helium-ion implantation, a standard industry technology, to precisely compensate the hole doping of GaAs-based diluted ferromagnetic semiconductors while keeping the Mn concentration constant. We monitor the change of Curie temperature (TC) and conductivity. For a broad range of samples including (Ga,Mn)As and (Ga,Mn)(As,P) with various Mn and P concentrations, we observe a smooth decrease of TC with carrier compensation over a wide temperature range while the conduction is changed from metallic to insulating. The existence of TC below 10 K is also confirmed in heavily compensated samples. Our experimental results are naturally explained within the valence-band picture. American Physical Society 2016-08-15 Article PeerReviewed Zhou, Shengqiang, Li, Lin, Yuan, Ye, Rushforth, A.W., Chen, Lin, Wang, Yutian, Böttger, R., Heller, R., Zhao, Jianhua, Edmonds, K.W., Campion, R.P., Gallagher, B.L., Timm, C. and Helm, M. (2016) Precise tuning of the Curie temperature of (Ga,Mn)As-based magnetic semiconductors by hole compensation: Support for valence-band ferromagnetism. Physical Review B, 94 (7). 075205-1. ISSN 2469-9969 http://journals.aps.org/prb/abstract/10.1103/PhysRevB.94.075205 doi:10.1103/PhysRevB.94.075205 doi:10.1103/PhysRevB.94.075205 |
| spellingShingle | Zhou, Shengqiang Li, Lin Yuan, Ye Rushforth, A.W. Chen, Lin Wang, Yutian Böttger, R. Heller, R. Zhao, Jianhua Edmonds, K.W. Campion, R.P. Gallagher, B.L. Timm, C. Helm, M. Precise tuning of the Curie temperature of (Ga,Mn)As-based magnetic semiconductors by hole compensation: Support for valence-band ferromagnetism |
| title | Precise tuning of the Curie temperature of (Ga,Mn)As-based magnetic semiconductors by hole compensation: Support for valence-band ferromagnetism |
| title_full | Precise tuning of the Curie temperature of (Ga,Mn)As-based magnetic semiconductors by hole compensation: Support for valence-band ferromagnetism |
| title_fullStr | Precise tuning of the Curie temperature of (Ga,Mn)As-based magnetic semiconductors by hole compensation: Support for valence-band ferromagnetism |
| title_full_unstemmed | Precise tuning of the Curie temperature of (Ga,Mn)As-based magnetic semiconductors by hole compensation: Support for valence-band ferromagnetism |
| title_short | Precise tuning of the Curie temperature of (Ga,Mn)As-based magnetic semiconductors by hole compensation: Support for valence-band ferromagnetism |
| title_sort | precise tuning of the curie temperature of (ga,mn)as-based magnetic semiconductors by hole compensation: support for valence-band ferromagnetism |
| url | https://eprints.nottingham.ac.uk/37051/ https://eprints.nottingham.ac.uk/37051/ https://eprints.nottingham.ac.uk/37051/ |