부산대학교 도서관

The temperature dependence of the microwave complex conductivity σ(T)=σ1(T)-iσ1(T) was determined at 9.6 and 14 GHz in a single crystal of CeNiSn from the surface impedance measurements. Below about 10 K the real part σ1 is suppressed in comparison with the dc conductivity and the imaginary part σ2 increases rapidly. These results indicate a rapid decrease of scattering of quasiparticles, whose excitation spectrum is drastically changed from the heavy-fermion to a gapped state at low temperatures.