Year: 2020
Type: article
Abstract: We analytically calculate the anomalous transverse electric and thermal currents in massive and tilted Dirac systems, using β-borophene as a representative material, and report on conditions under which the corresponding Lorenz number (Lan) deviates from its classically accepted value (L0). The deviations in the high-temperature regime are shown to be an outcome of the quantitative difference in the respective kinetic transport expressions for electric (σ) and thermal (κ) conductivity and are further weighted through a convolution integral with a non-linearly energy-dependent Berry curvature that naturally arises in a Dirac material. In addition, the tilt and anisotropy of the Dirac system that are amenable to change via an external stimulus are found to quantitatively influence Lan. The reported deviations from L0 hold practical utility inasmuch as they allow an independent tuning of σ and κ, useful in optimizing the output of thermoelectric devices.
Source: Applied Physics Letters
DOI: 10.1063/5.0028959
Authors: Parijat Sengupta, Enrico Bellotti
Institutions: Boston University, Purdue University West Lafayette
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funder: Army Research Laboratory
Award: G620260647
OpenAlex ID: W3082583741