Room temperature ferromagnetism and hopping transport in amorphous CrN thin films

• Published in: Thin solid films 2011-01, Vol.519 (6), p.1989-1992
• Main Authors: Zhou, Zhongpo, Luo, Shijun, Wang, Yin, Ai, Zhiwei, Liu, Chang, Wang, Duofa, Lee, YoungPak
• Format: Article
• Language: English
• Subjects: Chromium nitride; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport; Exact sciences and technology; Ferromagnetic materials; Ferromagnetism; Magnesium oxide; Magnetic properties; Magnetic properties and materials; Magnetic properties of monolayers and thin films; Magnetic properties of surface, thin films and multilayers; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Molecular beam epitaxy; Molecular, atomic, ion, and chemical beam epitaxy; Physics; Physics of gases, plasmas and electric discharges; Physics of plasmas and electric discharges; Plasma applications; Polarons; Resistivity; Surface and interface electron states; Thin films; Transmission electron microscopy
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2010.10.070

Magnetic and electronic properties of stoichiometric amorphous CrN thin films grown on MgO (001) substrates by radio-frequency nitrogen-plasma-assisted molecular beam epitaxy have been investigated. The magnetic property of the amorphous CrN thin films shows a ferromagnetic behavior even at room temperature, and can be interpreted by the percolation theory of magnetic polaron where we consider Cr3+ defects as magnetic impurities which lead to the formation of bound magnetic polarons. The obtained results of electrical conductivity are explained by the variable-range-hopping theory of the Mott and Davis model.