Figure 3
From: Spin–orbit torques in normal metal/Nb/ferromagnet heterostructures
Comparison of the polarity of the second harmonic signal and current-induced SOT switching. (a, c) Second harmonic signal of the Ta/Nb (a) and Pt/Nb series (c), respectively. The sign change occurs when the thickness of Nb exceeds 3 nm in Pt/Nb, but there was no such change in Ta/Nb series. (b, d) Current induced-SOT switching curve of the Ta/Nb (b) and Pt/Nb series (d).
