Spin Seebeck effect at low temperatures in the nominally paramagnetic insulating state of vanadium dioxide
Renjie Luo, Xuanhan Zhao, Liyang Chen, Tanner J. Legvold, Henry Navarro, Iván K. Schuller, Douglas Natelson
Abstract
The low temperature monoclinic, insulating phase of vanadium dioxide is ordinarily considered nonmagnetic, with dimerized vanadium atoms forming spin singlets, though paramagnetic response is seen at low temperatures. We find a nonlocal spin Seebeck signal in VO2 films that appears below 30 K and that increases with a decrease in temperature. The spin Seebeck response has a nonhysteretic dependence on the in-plane external magnetic field. This paramagnetic spin Seebeck response is discussed in terms of prior findings on paramagnetic spin Seebeck effects and expected magnetic excitations of the monoclinic ground state.
Topics & Concepts
ParamagnetismCondensed matter physicsMonoclinic crystal systemSeebeck coefficientSpin (aerodynamics)Thermoelectric effectMaterials scienceVanadiumChemistryPhysicsCrystal structureCrystallographyThermodynamicsMetallurgyTransition Metal Oxide NanomaterialsMagneto-Optical Properties and ApplicationsAdvanced Memory and Neural Computing