Effect of magnetic anisotropy on spin-dependent thermoelectric effects in nanoscopic systems

Abstract

Conventional and spin-related thermoelectric effects in electronic transport through a nanoscopic system exhibiting magnetic anisotropy $-$with both uniaxial and transverse components$-$ are studied theoretically in the linear response regime. In particular, a magnetic tunnel junction with a large-spin impurity $-$either a magnetic atom or a magnetic molecule$-$ embedded in the barrier is considered as an example. Owing to magnetic interaction with the impurity, conduction electrons traversing the junction can scatter on the impurity, which effectively can lead to angular momentum and energy exchange between the electrons and the impurity. As we show, such processes have a profound effect on the thermoelectric response of the system. Specifically, we present a detailed analysis of charge, spin and thermal conductance, together with the Seebeck and spin Seebeck coefficients (thermopowers). Since the scattering mechanism also involves processes when electrons are inelastically scattered back to the same electrode, one can expect the flow of spin and energy also in the absence of charge transport through the junction. This, in turn, results in a finite spin thermopower, and the magnetic anisotropy plays a key role for this effect to occur.

23 pages with 16 figures; version as published

References in corpus (11)

• Spin Seebeck insulator
• Observation of the Spin-Seebeck Effect in a Ferromagnetic Semiconductor
• Theory of magnon-driven spin Seebeck effect
• Electric Field Controlled Magnetic Anisotropy in a Single Molecule
• Thermoelectric Effects in Magnetic Nanostructures
• Berry Phase Oscillations of the Kondo Effect in Single-Molecule Magnets
• Many-body theory of electronic transport in single-molecule heterojunctions
• Berry-phase blockade in single-molecule magnets
• Spin-dependent Seebeck effect in non-local spin valve devices
• Probing Transverse Magnetic Anisotropy by Electronic Transport through a Single-Molecule Magnet
• Spin-dependent thermoelectric effects in transport through a nanoscopic junction involving spin impurity

Cited by in corpus (6)

• Large thermoelectric power and figure of merit in a ferromagnetic-quantum dot-superconducting device
• Spin-resolved thermal signatures of Majorana-Kondo interplay in double quantum dots
• Spin-dependent heat signatures of single-molecule spin dynamics
• Spin Seebeck effect of correlated magnetic molecules
• Spin transport through a nanojunction with a precessing anisotropic molecular spin: Quantum interference and spin-transfer torque
• Effect of uniaxial magnetic anisotropy on charge transport in a junction with a precessing anisotropic molecular spin