Spin-Caloritronic Batteries

Abstract

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.

Topological nonlinear anomalous Nernst effect in strained transition metal dichalcogenides

“…Monolayer MoS 2 and other transition-metal dichalcogenides (TMDCs) represent a new class of twodimensional (2D) materials, intrinsically behaving as semiconductors. Due to lack of an inversion center, their nonvanishing Berry curvature in each valley and strong spin-orbit coupling (SOC) lead to a series of valley and spin related anomalous transport phenomena, such as valley (spin) Hall effect [18][19][20] and valley (spin) Nernst effect [21,22]. However, H-structure monolayer TMDCs cannot host linear and nonlinear currents flowing transverse to the driving forces (electric field or temperature gradient) due to the presence of time reversal and C 3v symmetry [10,23].…”

Temperature dependence of the mean magnon collision time in a spin Seebeck device

“…The use of Pt as a metallic layer permits to detect the magnetic moment current because of the inverse spin Hall effect that laterally deflects polarized electrons and creates an electric voltage in the transverse direction [1]. In the last decade the spin Seebeck effect has attracted attention as an alternative thermoelectric generator and as a source of a magnetic moment current for spintronic devices without involving a charge current [2,3]. However, to optimize the effect, the underlying physics needs to be appropriately understood.…”

Experimental proof of the reciprocal relation between spin Peltier and spin Seebeck effects in a bulk YIG/Pt bilayer

“…One of the key building blocks for "spintronic circuits" is the spin battery, a device which can drive a spin current into an external circuit. Spin batteries are fundamental for spintronic devices and may be developed exploiting spincaloritronic effects [9]. Spincaloritronic devices may also be used in the development of novel thermoelectric heaters/coolers operating at the microscale [10,11].…”