Topological protection and glassiness in a non-centroysmmetric magnet

Hexagonal and non-centrosymmetric ScFeGe was discovered to host an incommensurate helimagnetic state along the $c$-axis below 36 K that matches well with a nesting condition found in its electronic structure. The result is a highly itinerant transition metal magnet whose physical properties that displays many similarities to the largely local-moment rare earth metals. The transition to a fully polarized magnetic state for fields perpendicular to the $c$-axis is found to progress through a sharp metamagnetic transition to a fan state. The signature of this transition in the $dc$ magnetization at low temperatures is extraordinarily different from its low frequency $ac$ counterpart despite their quantitative agreement above 15 K. This change is accompanied by a distinct change in the specific heat from a step-like feature at low temperature to a second-order phase transition above 15 K. These data are interpreted as revealing a local topological protection of the chiral helimagnetic state despite the likely existence of right- and left-handed helimagnetic domains that nucleate upon cooling in zero magnetic field.