Nernst effect and Kondo scattering in (CeLa)Cu2Si2

P. Sun, C. Geibel, F. Steglich

MPI-CPfs, Dresden, Germany


    The Nernst effect is extremely sensitive to the relaxation-time spectra of quasi-particles as a function of energy.  By studying the Nernst effect and other electrical and thermoelectric properties of (CeLa)Cu2Si2 in magnetic fields, we hope to provide new insights into the Kondo scattering and its correlation with the enhanced thermoelectricity generally observed in heavy-fermion systems.  We observed an enhanced Nernst signal in a large temperature range up to room temperature for all the investigated (CeLa)Cu2Si2 samples except for LaCu2Si2.  The enhancement of the Nernst signals points to a large particle-hole asymmetry of the carrier relaxation time caused by the Kondo scattering, and can indeed account for a major part of the thermopower observed in the systems under investigation.  However, we found that other effects, like skew scattering, also largely affect the Nernst effect in Kondo systems.

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