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Elphick K, Frost W, Samiepour M, Kubota T, Takanashi K, Sukegawa H, Mitani S, Hirohata A. Heusler alloys for spintronic devices: review on recent development and future perspectives. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2021; 22:235-271. [PMID: 33828415 PMCID: PMC8009123 DOI: 10.1080/14686996.2020.1812364] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 08/17/2020] [Accepted: 08/17/2020] [Indexed: 05/14/2023]
Abstract
Heusler alloys are theoretically predicted to become half-metals at room temperature (RT). The advantages of using these alloys are good lattice matching with major substrates, high Curie temperature above RT and intermetallic controllability for spin density of states at the Fermi energy level. The alloys are categorised into half- and full-Heusler alloys depending upon the crystalline structures, each being discussed both experimentally and theoretically. Fundamental properties of ferromagnetic Heusler alloys are described. Both structural and magnetic characterisations on an atomic scale are typically carried out in order to prove the half-metallicity at RT. Atomic ordering in the films is directly observed by X-ray diffraction and is also indirectly probed via the temperature dependence of electrical resistivity. Element specific magnetic moments and spin polarisation of the Heusler alloy films are directly measured using X-ray magnetic circular dichroism and Andreev reflection, respectively. By employing these ferromagnetic alloy films in a spintronic device, efficient spin injection into a non-magnetic material and large magnetoresistance are also discussed. Fundamental properties of antiferromagnetic Heusler alloys are then described. Both structural and magnetic characterisations on an atomic scale are shown. Atomic ordering in the Heusler alloy films is indirectly measured by the temperature dependence of electrical resistivity. Antiferromagnetic configurations are directly imaged by X-ray magnetic linear dichroism and polarised neutron reflection. The applications of the antiferromagnetic Heusler alloy films are also explained. The other non-magnetic Heusler alloys are listed. A brief summary is provided at the end of this review.
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Affiliation(s)
- Kelvin Elphick
- Department of Electronic Engineering, University of York, York, UK
| | - William Frost
- Department of Electronic Engineering, University of York, York, UK
| | - Marjan Samiepour
- Department of Electronic Engineering, University of York, York, UK
- Seagate Technology,1 Disc Drive, Springtown Industrial Estate, Londonderry, Northern Ireland
| | - Takahide Kubota
- Institute for Materials Research, Tohoku University, Sendai, Japan
- Center for Spintronics Research Network, Tohoku University, Sendai, Japan
| | - Koki Takanashi
- Institute for Materials Research, Tohoku University, Sendai, Japan
- Center for Spintronics Research Network, Tohoku University, Sendai, Japan
- Center for Science and Innovation in Spintronics, Core Research Cluster, Tohoku University, Sendai, Japan
| | - Hiroaki Sukegawa
- Research Center for Magnetic and Spintronic Materials, National Institute for Materials Science, Tsukuba, Japan
| | - Seiji Mitani
- Research Center for Magnetic and Spintronic Materials, National Institute for Materials Science, Tsukuba, Japan
- Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan
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Wang HL, Yu XZ, Wang SL, Chen L, Zhao JH. Note: simultaneous measurements of magnetization and electrical transport signal by a reconstructed superconducting quantum interference device magnetometer. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:086103. [PMID: 24007123 DOI: 10.1063/1.4817623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We have developed a sample rod which makes the conventional superconducting quantum interference device magnetometer capable of performing magnetization and electrical transport measurements simultaneously. The sample holder attached to the end of a 140 cm long sample rod is a nonmagnetic drinking straw or a 1.5 mm wide silicon strip with small magnetic background signal. Ferromagnetic semiconductor (Ga,Mn)As films are used to test the new sample rod, and the results are in good agreement with previous report.
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Affiliation(s)
- H L Wang
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083, China
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