Abstract
We examine the thermal origin of the detected “saw-tooth” shaped Hall resistance (Rxy) signals in the spin–orbit torque switching experiment for antiferromagnetic MnN. Compared with the results of the heavy metal/antiferromagnet bilayers (MnN/Ta), the qualitatively same “saw-tooth” shaped signals also appear in the samples with the heavy metal layer alone (either Ta or Pt) without the MnN layer. In addition, the Rxy signal changes oppositely in the devices with Ta and Pt, due to the opposite temperature coefficient of resistivity of the two materials. All those results are consistent with the “localized Joule heating” mechanism in devices with Hall crosses geometry. Moreover, by utilizing a structure with separated writing current paths and Hall cross area, the quadratic relationship between ΔRxy and the writing current's amplitude is observed, which provides quantitative evidence of the thermal contribution. These results reveal the dominant thermal artifact in the widely used Hall crosses geometry for Néel vector probing and also provide a strategy to semi-quantitatively evaluate the thermal effect, which can shed light on a more conclusive experiment design.
Submitted Version (
Free)
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call