A Low-Field Temperature Dependent EPR Signal in Terraced MgO:Mn2+ Nanoparticles: An Enhanced Zeeman Splitting in the Wide-Bandgap Oxide. (19th January 2017)

• Record Type: Journal Article
• Authors: Pikhitsa, Peter V.; Chae, Sukbyung; Shin, Seungha; Choi, Mansoo
• Other Names: Garcia-Guinea Javier Academic Editor.
• Is Part Of: Journal of spectroscopy. Volume 2017(2017)
• Publication Date: 2017-01-19
• Subjects: Spectrum analysis -- Periodicals; 543.505
• DOI: 10.1155/2017/8276520
• Languages: English
• ISSNs: 2314-4920

Abstract

Abstract : Mn 2+ ion doping is used as an electron paramagnetic resonance (EPR) probe to investigate the influence of low-coordination structural defects such as step edges at the surface of terraced (001) MgO nanoparticles on the electronic properties. Beside the well-known hyperfine sextet of Mn 2+ ions in the cubic crystal field of MgO, an additional EPR feature with a striking nonmonotonous temperature dependent shift of the g -factor is observed in terraced nanoparticles in the temperature range from 4 K to room temperature. By linking the difference in the temperature dependence of the Mn 2+ sextet intensity in cubic and terraced nanoparticles with the possible s-d exchange shift and enhanced Zeeman splitting we conclude that the novel EPR feature originates from the loosely trapped charge-compensating carriers at the abundant structural defects at the surface of terraced nanoparticles due to their exchange interaction with neighboring Mn 2+ ions.