STSM of Miroslav Marcin at the LNCMI – French National High Magnetic Field Laboratory in Grenoble (France)

CeCoIn5 is a heavy fermion d-wave superconductor featuring various interesting properties. It is Pauli limited and its vortex lattice undergoes several phase transitions changing their arrangement from hexagonal to rhombic and square when varying temperature or applied magnetic field. Up to now our study was mainly focused on the superconducting state of this material. During my Short Term Scientific Mission I have complemented our research by a study of field-induced development of Fermi liquid regime in the normal state of this superconductor. The planned experiments were based on previously observed anomalous low temperature evolution of magnetoresistance. Using resistive ac-calorimetry method we have clearly observed changes in curvature of the temperature and magnetic field dependencies of the heat capacity, which are related to field-induced recovery of the Fermi liquid regime. Since calorimetry is a bulk method, our measurements confirmed that magnetic field evolution of the Fermi liquid behavior of this material has bulk origin.