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DOE OSTI · 2544216

Low-temperature spin Seebeck effect in nonmagnetic vanadium dioxide

Luo, Renjie·Legvold, Tanner J.·Chen, Liyang·Navarro, Henry·Basaran, Ali C.·Hong, Deshun·Liu, Changjiang·Bhattacharya, Anand·Schuller, Ivan K.·Natelson, Douglas
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Abstract

The spin Seebeck effect (SSE) is sensitive to thermally driven magnetic excitations in magnetic insulators. Vanadium dioxide in its insulating low-temperature phase is expected to lack magnetic degrees of freedom, as vanadium atoms are thought to form singlets upon dimerization of the vanadium chains. Instead, we find a paramagnetic SSE response in V⁢O 2 films that grows as the temperature decreases below 50 K. The field and temperature-dependent SSE voltage is qualitatively consistent with a general model of paramagnetic SSE response and inconsistent with triplet spin transport. Quantitative estimates find a spin Seebeck coefficient comparable in magnitude to that observed in strongly magnetic materials. Finally, the microscopic nature of the magnetic excitations in V⁢O 2 requires further examination.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYparamagnetsspin Seebeck effectstrongly correlated systems

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BibTeXRIS

Luo, Renjie, Legvold, Tanner J., Chen, Liyang, Navarro, Henry, Basaran, Ali C., Hong, Deshun, Liu, Changjiang, Bhattacharya, Anand, Schuller, Ivan K., Natelson, Douglas. 2024-07-11. Low-temperature spin Seebeck effect in nonmagnetic vanadium dioxide. https://doi.org/10.1103/physrevb.110.024415

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