Work

Thermal generation of spin current in a quantum dot coupled to magnetic insulators

Year: 2023

Type: article

Abstract: In this work we study thermally-generated spin current in the system consisting of a quantum dot connected to two magnetic insulators. The external leads are kept at different temperatures which leads to imbalance of magnon populations in two magnetic insulators resulting in flow of the magnon (spin) current. We take into account many-body magnon interactions and incorporate energy-dependent density of states of the magnetic insulators. Both features can strongly affect magnon distribution in the magnetic insulators and the coupling strengths between the leads and the dot, and thus, the thermally generated spin current. All the calculations are carried out in the weak coupling regime. We show, that results obtained with density of states being function of energy differ significantly from the one obtained with density of states taken as a constant. In turn, magnon interactions in the leads proved to be important at high temperatures and large values of energy of transported spin waves. Highlights Energy-dependent density of states is an important factor influencing thermal generation of spin current.Magnon-magnon interactions affect transport properties when the temperature approaches room temperature and when the energy of transported magnons is sufficiently high.

Source: Journal of Magnetism and Magnetic Materials

DOI: 10.1016/j.jmmm.2023.171495

Authors: Emil Siuda, Piotr Trocha

Institution: Adam Mickiewicz University in Poznań

Language: English

Topic: Quantum and electron transport phenomena

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,000

Funders: Narodowe Centrum Nauki, Uniwersytet im. Adama Mickiewicza w Poznaniu