We have studied the complex conductivity in superconducting and normal metallic states of CeRu2 by the surface impedance measurements at millimeter-wave frequency of 45.4 GHz. The temperature dependence of the complex conductivity below Tc = 6.2 K exhibits the characteristic behaviors as seen in a conventional superconductor. The coherence peak observed in the real part σ1 provides a strong evidence for a conventional s-wave superconductivity as well as the previous NQR measurements. The temperature dependence of the penetration depth evaluated from the surface reactance at low temperatures has revealed the ratio of 2Δ(0)/kBTc = 4.4. The strong-coupling theories suggest the electron-phonon coupling strength with λep < 2. These results indicate that CeRu2 is an intermediate strong-coupling superconductor in a clean limit.
|Number of pages||5|
|Journal||journal of the physical society of japan|
|Publication status||Published - 1998 Oct|
- Penetration depth
ASJC Scopus subject areas
- Physics and Astronomy(all)