Nmr Studies On Heavy Fermion And Conventional Metal Superlattices Cecoin5/Ybcoin5

We performed nuclear magnetic resonance (NMR) experiments on heavy fermion and conventional metal superlattices CeCoIn5/YbCoIn5. We succeeded in identifying the signals arising from CeCoIn5 and YbCoIn5 block layers (BLs) by comparing the spectra of the CeCoIn5/YbCoIn5 superlattices, CeCoIn5 thin film, and YbCoIn5 thin film. Furthermore, we found that the signals of Ce-BLs could be divided into signals arising from interfacial layers and inner layers even in one Ce-BL by comparing the spectra of two CeCoIn5/YbCoIn5 superlattices with different thickness of the Ce-BLs. A comparison of the spectra of the superlattices with different Ce-BL thickness and field dependence of nuclear-spin lattice relaxation rate 1/T-1 indicate that antiferromagnetic spin fluctuations at the interfacial site are more suppressed than those at the inner layer site even in the Ce-BLs.