Phase diagram of CeRh₂Si₂ under pressure studied by thermopower measurements

We report the evolution of thermoelectric power under hydrostatic pressure up to 17 kbar and at low temperature in the heavy fermion compound CeRh₂Si₂. These measurements were performed using a thermoelectric setup specially designed for piston cylinder pressure cells. The suppression of the antiferromagnetic order (AF) into a paramagnetic order (PM) state was studied and the (T, P) phase diagram was precisely obtained. The different magnetic transitions at low temperature as a function of pressure, AF₁-AF₂ transition at P'_c and AF₁-PM transition at P_c, show significant changes in the thermoelectric signal. This support reconstructions of the Fermi surface in agreement with previous de Haas van Alphen experiments.