Electronic structure and spin fluctuations in the helical ferromagnet MnSi / Povzner A. A.,Volkov A. G.,Yasyulevich I. A. // PHYSICS OF THE SOLID STATE. - 2016. - V. 58, l. 7. - P. 1325-1331.

ISSN/EISSN:

1063-7834 / 1090-6460

Type:

Article

Abstract:

The influence of spin fluctuations on the magnetic properties of the ferromagnetic helimagnet MnSi has been studied in the Hubbard model taking into account the antisymmetric relativistic Dzyaloshinskii-Moriya interaction for band electrons. The obtained equations of the magnetic state indicate the correlation between the fine structure of the density of electronic states and the magnetization and coefficient of mode-mode coupling. It has been shown that the position of the Fermi energy in the immediate proximity on the point of the local minimum of the density of electronic states leads to large zero spin fluctuations at low magnetization of the helimagnet. When approaching from down the N,el point (approximately, at 0.9T (N)), the zero fluctuation disappear, and the temperature rise of thermal spin fluctuation is accompanied by the change in the sign of the coefficient of mode-mode coupling. A magnetic field perpendicular to the helicoids plane brings about the formation and subsequent ``collapse{''} of the helimagnetic cone. However, the condition of the change in the sign of the coefficient of mode-mode coupling divides the MnSi phase diagram into two parts, one of which corresponds to the ferromagnetic state induced by the field, and the other corresponding to the paramagnetic state. In this case, the h-T diagram has a specific region, inside which the paramagnetic and the ferromagnetic state are instable. The boundaries of the region agree with the experimental data on the boundaries of the anomalous phase (a phase). It has been found that the results of calculations of the temperature dependence of the magnetic susceptibility agree with the experimental data.

Author keywords:

QUANTUM PHASE-TRANSITION

DOI:

10.1134/S1063783416070295

Web of Science ID:

ISI:000380272500008

Соавторы в МНС:

Другие поля

Поле	Значение
Month	JUL
Publisher	MAIK NAUKA/INTERPERIODICA/SPRINGER
Address	233 SPRING ST, NEW YORK, NY 10013-1578 USA
Language	English
EISSN	1090-6460
Keywords-Plus	QUANTUM PHASE-TRANSITION
Research-Areas	Physics
Web-of-Science-Categories	Physics, Condensed Matter
Author-Email	a.a.povzner@urfu.ru
ResearcherID-Numbers	Povzner, Aleksandr/A-4625-2016
Number-of-Cited-References	17
Usage-Count-Last-180-days	3
Usage-Count-Since-2013	15
Journal-ISO	Phys. Solid State
Doc-Delivery-Number	DS0GD