Quasi Static Remanence in Dzyaloshinskii-Moriya Interaction driven Weak Ferromagnets and Piezomagnets

Abstract

We explore remanent magnetization ($\mu$) as a function of time and temperature, in a variety of rhombohedral antiferromagnets (AFM) which are also weak ferromagnets (WFM) and piezomagnets (PzM). These measurements, across samples with length scales ranging from nano to bulk, firmly establish the presence of a remanence that is quasi static in nature and exhibits a counter-intuitive magnetic field dependence. These observations unravel an ultra-slow magnetization relaxation phenomenon related to this quasi static remanence. This feature is also observed in a defect free single crystal of $\alpha$-Fe${}_2$O${}_3$, which is a canonical WFM and PzM. Notably, $\alpha$-Fe${}_2$O${}_3$ is not a typical geometrically frustrated AFM and in single crystal form, it is also devoid of any size or interface effects, which are the usual suspects for a slow magnetization relaxation phenomenon. The underlying pinning mechanism appears exclusive to those AFM which are either symmetry allowed WFM, driven by Dzyaloshinskii-Moriya Interaction (DMI) or can generate this trait by tuning of size and interface. The qualitative features of the quasi static remanence indicate that such WFM are potential piezomagnets, in which magnetization can be tuned by \textit{stress} alone.

References in corpus (6)

• Spontaneous Skyrmion Ground States in Magnetic Metals
• Observation of the Magnon Hall Effect
• Theory of the helical spin crystal: a candidate for the partially ordered state of MnSi
• Dzyaloshinskii-Moriya interaction and Hall effects in the skyrmion phase of MnFeGe alloys
• Direct measurement of interfacial Dzyaloshinskii-Moriya interaction in X/CoFeB/MgO heterostructures with a scanning-NV magnetometer
• Effect of Dzyaloshinski-Moriya interaction on spin-polarized neutron scattering

Cited by in corpus (3)

• Weak Ferromagnetism and Time-Stable Remanence in Hematite: Effect of Shape, Size and Morphology
• Enhanced Magnetism & Time - Stable Remanence at the Interface of Hematite and Carbon Nanotubes
• Glucose Sensing Using Pristine and Co-doped Hematite Fiber-Optic sensors: Experimental and DFT Analysis