Spin-Caloritronic Batteries
Xiao-Qin Yu,¹ Zhen-Gang Zhu,^1,2,5,* Gang Su,^2,3,5,† and A.-P. Jauho^4,‡
1School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
²Theoretical Condensed Matter Physics and Computational Materials Physics Laboratory, College of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
³Kavli Institute of Theoretical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
⁴Center for Nanostructured Graphene (CNG), DTU Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
⁵CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing 100190, China
(Received 4 May 2017; revised manuscript received 9 August 2017; published 20 November 2017)

The thermoelectric performance of a topological energy converter is analyzed. The H-shaped device is based on a combination of transverse topological effects involving the spin: the inverse spin Hall effect and the spin Nernst effect. The device can convert a temperature drop in one arm into an electric power output in the other arm. Analytical expressions for the output voltage, the figure of merit (ZT), and energyconverting efficiency are reported. We show that the output voltage and the ZT can be tuned by the geometry of the device and the physical properties of the material. Importantly, contrary to a conventional thermoelectric device, here a low electric conductivity may, in fact, enhance the ZT value, thereby opening a path to strategies in optimizing the figure of merit.