First harmonic measurements of the spin Seebeck effect

Journal Article · 12 November 2018 · Applied Physics Letters

DOI: https://doi.org/10.1063/1.5053120 · OSTI ID:1613044

Chen, Yizhang ^[1]; Roy, Debangsu ^[2]; Cogulu, Egecan ^[2]; Chang, Houchen ^[3]; Wu, Mingzhong ^[3]; Kent, Andrew D. ^[2]

---

1. New York Univ. (NYU), NY (United States). Dept. of Physics; DOE/OSTI
2. New York Univ. (NYU), NY (United States). Dept. of Physics
3. Colorado State Univ., Fort Collins, CO (United States). Physics Dept.

We present measurements of the spin Seebeck effect (SSE) by a technique that combines alternating currents (AC) and direct currents (DC). The method is applied to a ferrimagnetic insulator/heavy metal bilayer, Y₃Fe₅O₁₂ (YIG)/Pt. Typically, SSE measurements use an AC current to produce an alternating temperature gradient and measure the voltage generated by the inverse spin-Hall effect in the heavy metal at twice the AC frequency. Here, we show that when Joule heating is associated with AC and DC bias currents, the SSE response occurs at the frequency of the AC current drive and can be larger than the second harmonic SSE response. We compare the first and second harmonic responses and show that they are consistent with the SSE. The field dependence of the voltage response is used to distinguish between the damping-like and field-like torques. This method can be used to explore nonlinear thermoelectric effects and spin dynamics induced by temperature gradients.

• Research Organization: Colorado State Univ., Fort Collins, CO (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• Grant/Contract Number: SC0018994
• OSTI ID: 1613044
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 20 Vol. 113; ISSN 0003-6951
• Publisher: American Institute of Physics (AIP)Copyright Statement
• Country of Publication: United States
• Language: English