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تسجيل مستخدم جديدCrossover from Karplus-Luttinger to Topological Hall Effects in SrRuO3-based heterostructures
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Using SrRuO3-based thin film heterostructures, we aim to resolve the two debated interpretations that distinguish between the genuine Topological Hall Effect (THE) and the artefactual humps produced from overlapping double Karplus-Luttinger Anomalous Hall Effects (KL-AHE), without magnetic imaging. Firstly, we selected two heterostructures with similar Hall Effect but with contrasting octahedral rotations/tilts, providing a clue to determining the presence/absence of Dzyaloshinskii-Moriya Interaction. Secondly, we employ the {theta}-rotation of magnetic field from out-of-plane to in-plane as the critical judgemental tool. The first heterostructure showing field-position of Hall hump diverging with ~1/cos({theta}) is correctly reproduced using the double KL-AHEs. Yet, the second one showing constant hump field versus {theta} behaviour agrees with a micromagnetic simulation with Neel-Skyrmions and is thus convincingly assigned as THE. Lastly, for a general system evolving with increasing magnetic field from two-dimensional Skyrmion-lattice into collinear ferromagnetic in the real-space, we further discuss about the corresponding evolution of k-space band structure from gapped massive Dirac Fermion into Weyl Fermion, consistent to past literatures. Its associated transformation from Mirror Anomaly into Chiral Anomaly is detectable via electrical transport and further assisted in resolving the aforementioned debate. We hence emphasize the two schemes as useful, generic electrical measurement protocols for future search of magnetic Skyrmions.
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