A straightforward 2ω technique for the measurement of the Thomson effect

Isaac Haïk Dunn (1) , Ramzy Daou (1) , Colin Atkinson (2, 3)

1 CRISMAT - Laboratoire de cristallographie et sciences des matériaux
2 Department of Mathematics [Imperial College London]
3 CAM - University of Cambridge [UK]

We present a simplified, rapid, and accurate method for the measurement of the thermoelectric Thomson coefficient by the dynamical heating of a suspended wire by an alternating current. By applying a temperature gradient across the wire, we find that the response at the second harmonic of the excitation frequency is directly proportional to the Thomson coefficient. The absolute thermoelectric coefficient of a single material can therefore be extracted with high precision by using a phase sensitive detector. We test our method on platinum and nickel wires and develop both analytical and numerical models to determine the leading sources of error.

Mots clés: Series expansion; Numerical methods; Thermal conductivity; Electric currents; Thermoelectric effects; Finite-element analysis; Alternating-current bridge; Resistivity measurements; Transition metals

Domaines: Science des matériaux [cond-mat.mtrl-sci]; Instrumentations et Détecteurs [physics.ins-det]

Isaac Haïk Dunn, Ramzy Daou, Colin Atkinson. A straightforward 2ω technique for the measurement of the Thomson effect. Review of Scientific Instruments, 2019, 90 (2), pp.024902-1-024902-11. ⟨10.1063/1.5055826⟩. ⟨hal-02109793⟩