Spin-disorder intervened avoidance of quantum criticality in B20 cubic Mn 1-x V x Si.

The effect of negative chemical pressure with the substitution of transition metal V in an itinerant helimagnetically ordered MnSi, Mn 1- x V x Si with x = 0-0.1, is explored using dc and ac-susceptibilities. With increasing x , the manifestations are unaffected crystal structure with increasing unit cell volume, suppression of long-range magnetic order, weakening of itinerant character and reduced spin-cooperative phenomenon. The emergence of spin-glass behaviour for x ≥ 0.1 intervenes in the occurrence of quantum phase transition. The constructed concentration-temperature x - T phase diagram illustrates the substitution-driven changes in the magnetism of MnSi. Further, the study suggests that the presence of a precursor state can favour the formation of spin-textures in magnetically ordered compositions 0 < x ≤ 0.05 below the ordering temperature.