The 80th JSAP Autumn Meeting 2019

Presentation information

Oral presentation

10 Spintronics and Magnetics » 10.1 Emerging materials in spintronics and magnetics (including fabrication and charactrization methodologies)

[20a-E216-1~6] 10.1 Emerging materials in spintronics and magnetics (including fabrication and charactrization methodologies)

Fri. Sep 20, 2019 9:00 AM - 10:30 AM E216 (E216)

Tomoyasu Taniyama(Nagoya Univ.)

9:15 AM - 9:30 AM

[20a-E216-2] Enhancement of the Nernst effect in magnetically coupled Co/Au/Fe multilayer

〇(PC)Himanshu Sharma1,2, Masaki Mizuguchi1,2,3 (1.IMR, Tohoku Univ., 2.CREST, JST Agency, 3.CSRN, Tohoku Univ.)

Keywords:Anomalous Nernst effect (ANE), Interlayer magnetic coupling (IMC), Metallic heterostructures

Spin caloritronics is a research field which is attributed to the simultaneous interaction of several physical parameters, viz., charge, spin, heat and spin-currents, which are initiated by thermal gradients in magnetic nanostructures. The emerging field of spin caloritronics combines spintronics and thermoelectrics and provides a variety of new effects, might enable waste heat recovery in memory and sensor devices [1-6]. On the other hand, two ferromagnetic layers separated by a thin nonmagnetic spacer can be exchange-coupled. Recently, the enhancement of anomalous Nernst effect (ANE) is observed in non-magnet/ferromagnet (NM/FM) multilayer systems by increasing the number of the interfaces, but keeping the total thickness of the multilayer constant [6-7]. However, the microscopic origin of this enhancement in ANE of these metallic multilayers still remains to be clarified, which augment the interest to investigate role of interlayer magnetic coupling (IMC) in FM/NM/FM system as a manner to enhance the ANE.
Here, we present the investigation of the effect of IMC on the ANE in Co/Au/Fe, multilayer with varying the thickness of spacer (Au) and top layer (Fe thin film). We deposited the thin films of heterostructures (see Fig. 1b) in situ using sputtering. Transport and thermoelectric properties were systematically measured using PPMS. The transverse Seebeck coefficient (Sxy) measured with out-of-plane thermal gradient for Co(4nm)/Au(2nm)/Fe(4 and 7nm) with varying number of trilayer (N) clearly shows enhancement of ANE with increasing N (see Fig. 1a). The effect of IMC on the ANE in Co/Au/Fe multilayer will be also presented in details.