F. Laliberté, PhD thesis

Thermoelectrical properties of correlated materials are measured in order to determine the electronic structure and the strength of electronic correlations. The technique requires application of a thermal gradient across the sample, and measurements of the induced voltage. When a magnetic ffield is applied, Nernst (transverse voltage ) and magneto-Seebeck (longitudinal voltage) effect can be measured.

As example we show the Seebeck effect, S, measured in the newly discovered superconducting material UTe2.  This paramagnetic system shows extraordinary phenomenon such as re-entrant superconductivity, i.e. the ability to induce superconductivity with a magnetic field. In high magnetic field the thermopower uncovers several electronic instabilities, indicated by arrows. Some of these features are attributed to so-called Lifshitz transition, a transition where the Fermi surface topology changes abruptly. Click here for more details on thermopower in UTe2.

Static field
Bmax 36 T
Temperature range 0.3 K - 300 K