Particles–Matrix Bond in ZnCoO:H and ZnCoAlO:H Films: Issues of Magnetism and Spin Injection
ZnCoO:H and ZnCoAlO:H films were synthesized by radio frequency magnetron sputtering in a (1 − x)Ar + xH<sub>2</sub> mixed atmosphere with x = 0.2–0.5. The films contain different amounts of metallic Co particles (from 7.6% and higher) ~4–7 nm in size. The magnetic and magneto-optical (M...
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| author | Yu. E. Samoshkina M. V. Rautskii D. S. Neznakhin E. A. Stepanova I. S. Edelman Hsiung Chou |
| author_facet | Yu. E. Samoshkina M. V. Rautskii D. S. Neznakhin E. A. Stepanova I. S. Edelman Hsiung Chou |
| author_sort | Yu. E. Samoshkina |
| collection | DOAJ |
| description | ZnCoO:H and ZnCoAlO:H films were synthesized by radio frequency magnetron sputtering in a (1 − x)Ar + xH<sub>2</sub> mixed atmosphere with x = 0.2–0.5. The films contain different amounts of metallic Co particles (from 7.6% and higher) ~4–7 nm in size. The magnetic and magneto-optical (MO) behavior of the films was analyzed in combination with their structural data. The samples exhibit high values of magnetization (up to 377 emu/cm<sup>3</sup>) and MO response at room temperature. Two situations are considered: (1) the film magnetism is associated only with isolated metal particles and (2) magnetism is present both in the oxide matrix and in metal inclusions. It has been established that the formation mechanism of the magnetic structure of ZnO:Co<sup>2+</sup> is due to the spin-polarized conduction electrons of metal particles and zinc vacancies. It was also found that in the presence of two magnetic components in the films, these components are exchange-coupled. In this case, the exchange coupling generates a high spin polarization of the films. The spin-dependent transport properties of the samples have been studied. A high value of the negative magnetoresistance of the films at room temperature (~4%) was found. This behavior was explained in terms of the giant magnetoresistance model. Thus, the ZnCoO:H and ZnCoAlO:H films with high spin polarization can be considered as sources of spin injection. |
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| language | English |
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| spelling | doaj.art-404e14812c924f73a2840e1deb1c28432023-11-18T02:14:13ZengMDPI AGMaterials1996-19442023-05-011610365910.3390/ma16103659Particles–Matrix Bond in ZnCoO:H and ZnCoAlO:H Films: Issues of Magnetism and Spin InjectionYu. E. Samoshkina0M. V. Rautskii1D. S. Neznakhin2E. A. Stepanova3I. S. Edelman4Hsiung Chou5Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, RussiaKirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, RussiaInstitute of Natural Sciences and Mathematics, Ural Federal University, 620002 Yekaterinburg, RussiaInstitute of Natural Sciences and Mathematics, Ural Federal University, 620002 Yekaterinburg, RussiaKirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, RussiaDepartment of Physics, National Sun Yat-sen University, Kaohsiung 80424, ChinaZnCoO:H and ZnCoAlO:H films were synthesized by radio frequency magnetron sputtering in a (1 − x)Ar + xH<sub>2</sub> mixed atmosphere with x = 0.2–0.5. The films contain different amounts of metallic Co particles (from 7.6% and higher) ~4–7 nm in size. The magnetic and magneto-optical (MO) behavior of the films was analyzed in combination with their structural data. The samples exhibit high values of magnetization (up to 377 emu/cm<sup>3</sup>) and MO response at room temperature. Two situations are considered: (1) the film magnetism is associated only with isolated metal particles and (2) magnetism is present both in the oxide matrix and in metal inclusions. It has been established that the formation mechanism of the magnetic structure of ZnO:Co<sup>2+</sup> is due to the spin-polarized conduction electrons of metal particles and zinc vacancies. It was also found that in the presence of two magnetic components in the films, these components are exchange-coupled. In this case, the exchange coupling generates a high spin polarization of the films. The spin-dependent transport properties of the samples have been studied. A high value of the negative magnetoresistance of the films at room temperature (~4%) was found. This behavior was explained in terms of the giant magnetoresistance model. Thus, the ZnCoO:H and ZnCoAlO:H films with high spin polarization can be considered as sources of spin injection.https://www.mdpi.com/1996-1944/16/10/3659thin filmszinc oxidemetallic Co nanoparticlesmagnetic propertiesmagnetic circular dichroism spectroscopygiant magnetoresistance effect |
| spellingShingle | Yu. E. Samoshkina M. V. Rautskii D. S. Neznakhin E. A. Stepanova I. S. Edelman Hsiung Chou Particles–Matrix Bond in ZnCoO:H and ZnCoAlO:H Films: Issues of Magnetism and Spin Injection Materials thin films zinc oxide metallic Co nanoparticles magnetic properties magnetic circular dichroism spectroscopy giant magnetoresistance effect |
| title | Particles–Matrix Bond in ZnCoO:H and ZnCoAlO:H Films: Issues of Magnetism and Spin Injection |
| title_full | Particles–Matrix Bond in ZnCoO:H and ZnCoAlO:H Films: Issues of Magnetism and Spin Injection |
| title_fullStr | Particles–Matrix Bond in ZnCoO:H and ZnCoAlO:H Films: Issues of Magnetism and Spin Injection |
| title_full_unstemmed | Particles–Matrix Bond in ZnCoO:H and ZnCoAlO:H Films: Issues of Magnetism and Spin Injection |
| title_short | Particles–Matrix Bond in ZnCoO:H and ZnCoAlO:H Films: Issues of Magnetism and Spin Injection |
| title_sort | particles matrix bond in zncoo h and zncoalo h films issues of magnetism and spin injection |
| topic | thin films zinc oxide metallic Co nanoparticles magnetic properties magnetic circular dichroism spectroscopy giant magnetoresistance effect |
| url | https://www.mdpi.com/1996-1944/16/10/3659 |
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