Related Experiment Video
Updated: Apr 25, 2026

Asymmetric Thermoelectrochemical Cell for Harvesting Low-grade Heat under Isothermal Operation
Published on: February 5, 2020
Strong bounds on Onsager coefficients and efficiency for three-terminal thermoelectric transport in a magnetic field
Kay Brandner1, Keiji Saito2, Udo Seifert1
1II. Institut für Theoretischen Physik, Universität Stuttgart, 70550 Stuttgart, Germany.
Abstract:
For thermoelectric transport in the presence of a magnetic field that breaks time-reversal symmetry, a strong bound on the Onsager coefficients is derived within a general setup using three terminals. Asymmetric Onsager coefficients lead to a maximum efficiency substantially smaller than the Carnot efficiency reaching only η(C)/4 in the limit of strong asymmetry. Related bounds are derived for efficiency at maximum power, which can become larger than the Curzon-Ahlborn value η(C)/2, and for a cooling device. Our approach reveals that in the presence of reversible currents the standard analysis based on the positivity of entropy production is incomplete without considering the role of current conservation explicitly.
More Related Videos
Related Concept Videos
Thermodynamic Potentials
The Hall Effect
Magnetic Fields
A magnetic field is defined by the force that a charged particle experiences...
Debye–Huckel–Onsager Conductance Equation
Torque On A Current Loop In A Magnetic Field
Consider a rectangular current-carrying loop containing N turns of wire, placed in a uniform magnetic field. The net force on a current-carrying loop...
Theory of Metallic Conduction
In this theory, Newton's second law of motion is used to determine the acceleration of an electron in the presence of an applied electric field. Then, its velocity is expressed via this acceleration.
An electron moves through the crystal, containing positive ions,...

