Work

Orbital order and electron itinerancy in CoV 2 O 4 and Mn 0.5 Co 0.5 V 2 O 4 from first principles

Year: 2020

Type: article

Abstract: In view of the recent experimental predictions of a weak structural transition in CoV 2 O 4 we explore the possible orbital order states in its low temperature tetragonal phases from first principles density functional theory calculations. We observe that the tetragonal phase with I 41/ amd symmetry is associated with an orbital order involving complex orbitals with a reasonably large orbital moment at vanadium sites while in the phase with I 41/ a symmetry, the real orbitals with quenched orbital moment constitute the orbital order. Further, to study the competition between orbital order and electron itinerancy we considered Mn 0.5 Co 0.5 V 2 O 4 as one of the parent compounds, CoV 2 O 4 , lies near itinerant limit while the other, MnV 2 O 4 , lies deep inside the orbitally ordered insulating regime. Orbital order and electron transport have been investigated using first principles density functional theory and Boltzmann transport theory in CoV 2 O 4 , MnV 2 O 4 and Mn 0.5 Co 0.5 V 2 O 4 . Our results show that as we go from MnV 2 O 4 to CoV 2 O 4 there is enhancement in the electron’s itinerancy while the nature of orbital order remains unchanged.

Source: Journal of Physics Condensed Matter

DOI: 10.1088/1361-648x/ab7e57

Authors: Jyoti Krishna, T Maitra

Institutions: Arizona State University, Indian Institute of Technology Roorkee

Language: English

Topic: Magnetic and transport properties of perovskites and related materials

Subfield: Electronic, Optical and Magnetic Materials

Field: Materials Science

Domain: Physical Sciences

Open Access status: green

Funders: Department of Science and Technology, Ministry of Science and Technology, India, Deutscher Akademischer Austauschdienst, Ministry of Education, India

Award: G3288336086