Images of a first order spin-reorientation phase transition in a metallic kagome ferromagnet
arXiv:1909.07768
Abstract
First order phase transitions, where one phase replaces another by virtue of a simple crossing of free energies, are best known between solids, liquids and vapours, but they also occur in a wide range of other contexts, including even elemental magnets. The key challenges are to establish whether a phase transition is indeed first order, and then to determine how the new phase emerges because this will determine thermodynamic and electronic properties. Here we meet both challenges for the spin reorientation transition in the topological metallic ferromagnet Fe3Sn2. Our magnetometry and variable temperature magnetic force microscopy experiments reveal that, analogous to the liquid-gas transition in the temperature-pressure plane, this transition is centred on a first order line terminating in a critical end point in the field-temperature plane. We directly image the nucleation and growth associated with the transition and show that the new phase emerges at the most convoluted magnetic domain walls for the high temperature phase and then moves to self organize at the domain centres of the high temperature phase. The dense domain patterns and phase coexistence imply a complex inhomogeneous electronic structure, which will yield anomalous contributions to the magnetic field- and temperature-dependent electrical conductivity.
arXiv comment14 pages, 8 figures
References in corpus (9)
- High temperature fractional quantum Hall states
- Massive Dirac fermions in a ferromagnetic kagome metal
- Anomalous Hall effect of ferromagnetic Fe3Sn2 single crystal with geometrically frustrated kagome lattice
- Giant anomalous Hall resistivity of the room temperature ferromagnet Fe3Sn2 - a frustrated metal with the kagome-bilayer structure
- X-ray Microdiffraction Images of Antiferromagnetic Domain Evolution in Chromium
- Magnetic Field Effect and Dielectric Anomalies at the Spin Reorientation Phase Transition of GdFe3(BO3)4
- Mesoscale magnetism at the grain boundaries in colossal magnetoresistive films
- Switchable Weyl nodes in topological Kagome ferromagnet Fe3Sn2
- Helicity-protected domain-wall magnetoresistance in ferromagnetic Weyl semimetal