Dynamics of chiral state transitions and relaxations in an FeGe thin plate via in situ Lorentz microscopy

Abstract

<p>Studying the magnetic transition between different topological spin textures in noncentrosymmetric magnets under external stimuli is an important topic in chiral magnetism.</p>

Comparative study of the structural and magnetic properties of Mn1/3NbS2 and Cr1/Hall1, Loudon2, Midgley3 et al. 2022Phys. Rev. Materials14180View full textAdd to dashboardCite

“…It has a 48-nm helical pitch in zero field, which increases as the helix continuously transforms into the CSL on application of an external field. The CSL and other magnetic textures [5,[17][18][19][20][21] can be imaged using Lorentz transmission electron microscopy (LTEM).…”

Stabilization and topological transformation of magnetic bubbles in disks of a kagome magnet

“…14,16,20 The random rotational sense is a common feature of skyrmion bubbles, caused by the absence of chiral interactions in centrosymmetric Fe 3 Sn 2 in contrast to the single-chirality skyrmions in chiral magnets. 8,38,46 A completely different dynamic process is observed (supplementary material Fig. S1) when the magnetic field slightly deviates from the normal axis of the disk plane (e.g., a % 5 ).…”

Emergence of Room Temperature Magnetotransport Anomaly in Epitaxial Pt/γ′-Fe4N/MgO Heterostructures toward Noncollinear Spintronics

“…Additionally, Figure i–k shows the room-temperature MFM images of Pt­(3 nm)/γ′-Fe 4 N­(3 nm)/MgO heterostructures at different OP magnetic fields from 0 to 1.5 kOe, where the magnetic bubble-like contrasts (red) against a uniform background (cyan) can be observed. In the inset of Figure i–k, enlarged MFM images from the square regions show that the number of magnetic bubble-like domains increases with the increasing magnetic field magnitude from 0 to 1.5 kOe, where the magnetic bubble-like domains should be equivalent to one or multiple skyrmions. , The magnetic bubble-like domains indicate that the noncollinear spin textures exist in Pt­(3 nm)/γ′-Fe 4 N­(3 nm)/MgO heterostructures at 300 K. Note that the hump peaks of Pt­(3 nm)/γ′-Fe 4 N­( ≤ 4 nm)/MgO heterostructures at 300 K (see Figure c,d) are not as sharp as the peaks reported in previous works, ,, which is attributed to the nonuniform distribution of the magnetic bubble-like domains with various sizes and irregular shapes (see Figure i–k). Therefore, the contrast humps in the ρ xy – H z curves can be attributed to the noncollinear spin textures induced by both Pt/γ′-Fe 4 N and γ′-Fe 4 N/MgO interfacial DMIs.…”

“…In the inset of Figure 5i−k, enlarged MFM images from the square regions show that the number of magnetic bubble-like domains increases with the increasing magnetic field magnitude from 0 to 1.5 kOe, where the magnetic bubble-like domains should be equivalent to one or multiple skyrmions. 21,66 The magnetic bubble-like domains indicate that the noncollinear spin textures exist in Pt(3 nm)/ γ′-Fe 4 N(3 nm)/MgO heterostructures at 300 K. Note that the hump peaks of Pt(3 nm)/γ′-Fe 4 N(t Fe N 4 ≤ 4 nm)/MgO heterostructures at 300 K (see Figure 5c,d) are not as sharp as the peaks reported in previous works, 21,67,68 which is attributed to the nonuniform distribution of the magnetic bubble-like domains with various sizes and irregular shapes (see Figure 5i Notes…”

“…Noncollinear spin textures in HM/FM systems originate from interfacial Dzyaloshinskii–Moriya interactions (DMIs), which are induced by a strong SOC from the HM layer and a broken inversion symmetry at the interface. − Common noncollinear spin textures include vortices, merons, and skyrmions, , which can be directly or indirectly demonstrated by experimental or computational methods. For instance, noncollinear spin textures can be directly observed by spin-polarized scanning tunneling microscopy, ,− magneto-optical Kerr microscopy, X-ray microscopy, Lorentz transmission electron microscopy, , spin-polarized low energy electron microscopy, and magnetic force microscopy (MFM) in HM/FM systems, − such as W/Mn, W/Fe, Pt/Co/AlO x , Ir/PdFe, and Fe/Ni/Cu heterostructures. , Moreover, Hall transport measurements or theoretical simulations can also indirectly determine the existence of noncollinear spin textures. − The emergence of skyrmions in HM/FM systems shows that a strong DMI is required to twist spins, such as Ir/Co/Pt (micromagnetic DMI coefficient D = 2.0 mJ/m 2 ), Pt/Co/Ta ( D = 1.3 mJ/m 2 ), and Pt/Co/MgO ( D = 2.05 mJ/m 2 ) …”