Magnetic behavior of Ru substituted skyrmion metal MnSi

Abstract

We report on the structural and magnetic properties of Ru substituted skyrmion metal MnSi i.e. Mn1-xRuxSi for the nominal compositions of 0 ≤ x ≤ 0.5. The composition-temperature x-T phase diagram illustrates the substitution-driven changes in the magnetic behavior. It is confirmed that the magnetic ordering temperature (para-to helimagnetic) Tr and the effective magnetic μeff moment decrease with increasing x. This indicates the suppression of magnetic order by the substitution of Ru in MnSi. However, the magnetic nature is sustained up to a concentration of about x = 0.1 above which the system exhibits spin-glass like nature as inferred from the negative Curie-Weiss temperature θCW, reduced magnetic moment (of the order 10-2 μB/f.u.) and linear M-H (at 2 K) in x = 0.5. Mn1-xRuxSi is found to avoid the quantum phase transition and exhibits a composition-driven magnetic to spin-glass like transition.

Spin-disorder intervened avoidance of quantum criticality in B20 cubic Mn 1−xVx Si

“…Conversely, the effect of negative chemical pressure as induced by replacing Si with Ge resulted in the increase of helical ordering temperature as reported in various experiments [5,26]. In MnSi, Cr, and Ru for Mn suppress T hel with increasing lattice constant [6,27]. While numerous theoretical and experimental studies have focused on MnSi electronic and magnetic behaviors under external pressure and chemical substitution, most have focused on creating positive pressure or on chemical substitutions at the Mn site.…”

“…Modifying magnetic materials through chemical substitution stands as a viable common approach to discovering novel phases, when compared to H and p applications. Chemical substitutions can induce positive or negative chemical pressures, depending on the atomic radii of the substituting elements [1][2][3][4][5][6][7].…”