arXiv subjects

F. V. Temnikov

Publications and source records attributed to F. V. Temnikov.

2 recordsLinked to original sources

arXiv2022

Interplay of the Jahn--Teller Effect and Spin-Orbit Coupling: The Case of Trigonal Vibronic Modes

We study an interplay between the orbital degeneracy and spin-orbit coupling giving rise to spin-orbital entangled states. As a specific example, we analyze the interaction of electrons occupying triply degenerate single-ion $t_{2g}$ levels with trigonal vibronic modes (the $t\otimes T$ problem). A more general problem of the electron-lattice interaction involving both tetragonal and trigonal vibrations is also considered. It is shown that the result of such interaction crucially depends on the occupation of $t_{2g}$ levels leading to either the suppression or enhancement of the Jahn-Teller effect by the spin-orbit coupling.

cond-mat.mtrl-sci↗

arXiv2019

Mechanism of ferromagnetic ordering of the Mn chains in CaMnGe$_2$O$_6$ clinopyroxene

The electronic and magnetic properties of clinopyroxene CaMnGe$_2$O$_6$ were studied using density function calculations within the GGA+U approximation. It is shown that anomalous ferromagnetic ordering of neighboring chains is due to a "common-enemy" mechanism. Two antiferromagnetic exchange couplings between nearest neighbours within the Mn-Mn chain and interchain coupling via two GeO$_4$ tetrahedra suppress antiferromagnetic exchange via single GeO$_4$ tetrahedron and stabilize ferromagnetic ordering of Mn chains.

cond-mat.mtrl-sci↗