Physics Properties In Kondo Lattice Compound CePt₃P And Misfit Compound?SeSn?_1.13?TaSe₂?

Owing to the strongly correlated d electrons,transition metal compounds display various intriguing physical properties such as magnetism,superconductivity and spin/charge density wave.The research on coexistence or competition of these ordering states are hot spots in condensed matter physics.Among the compounds with rare earth element cerium which contains 4felectrons,the Kondo coupling interaction between conduction electrons and 4f electrons is a key interaction to induce quantum phases transitions.This master degree thesis studied the physics properties of two different type compounds:one is a Ce-based compound CePt₃P with an antiperovskite structure,and the other one is a misfit compound superconductor containing the TaSe2 layer by performing systematic measurements of resistivity,magnetic susceptibility and specific heat.This thesis has five chapters.In Chapter 1 we introduce the Pt-based and Ce-based superconductors and related compounds,and the progress of properties in misfit superconductor compounds.Chapter 2 describe the experimental methods.In Chapter 3 we present the properties of transition metal compound CePt₃P which first successfully synthesized by us.Our study indicates that it is an AFM Kondo lattice compound.Two successive magnetic transitions of Ce 4 f moments are observed:the magnetic ordering at T_N1=3.0 K and the spin reorientation at T_N2=1.9 K.Although no superconductivity is observed in CePt₃P down to 0.5 K,this material presents an opportunity for inducing possible quantum phase transition by doping or pressuring.In Chapter 4 we represent the discovery of a new misfit compound superconductor ?SnSe?_1.13?TaSe₂?,T_c=2.3 K.The H_c2^ab?0?in ab plane is larger than Pauli paramagnetic limit,which may be a multi-band effect compound according to the good two-band fitting result.In the last chapter we give a summary and outlook to our study.