Disorder-enhanced spin polarization of the Zn1−xCoxO1−v concentrated magnetic semiconductor. Issue 10 (20th January 2016)

• Record Type: Journal Article
• Authors: Xu, T. S.; Ju, L.; Wang, Z.; Ren, C.; Kang, S. S.; Qiao, S. Z.; Li, T. X.; Yan, S. S.; Mei, L. M.
• Is Part Of: RSC advances. Volume 6:Issue 10(2016)
• Page Start: 8043
• Page End: 8047
• Publication Date: 2016-01-20
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c5ra20520d
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Amorphous concentrated magnetic semiconductor Zn0.32 Co0.68 O1−v (v refers to oxygen vacancies) thin film was investigated by magnetic and electrical transport measurements as well as Andreev reflection spectroscopy. Abstract : Amorphous concentrated magnetic semiconductor Zn0.32 Co0.68 O1−v (v refers to oxygen vacancies) thin film was investigated by magnetic and electrical transport measurements as well as Andreev reflection spectroscopy. At a low temperature range, the electrons in the Zn0.32 Co0.68 O1−v are strongly localized, and electrical transport obeys the Efros variable range hopping law. Spin polarization was measured by Andreev reflection spectroscopy. As high as 64 ± 5% of spin polarization was attained through fitting of the modified Blonder–Tinkham–Klapwijk (BTK) theory. This enhanced spin polarization of Zn0.32 Co0.68 O1−v likely relates with the structure disorder and high concentration of magnetic cobalt ions, which lead to a spin imbalance impurity band in the tail of the conduction band. Considering room temperature ferromagnetism and high spin polarization, this material appears to be promising for spintronics device applications.