Superconductivity in Y2Pd(Ge1-xSix)3 (x=0-1)

The electrical resistivity (2 - 300K), magnetization (2 - 10 K), and specific heat (0.5 - 10 K) were measured in Y2Pd(Ge1-xSix)(3), which is of AlB2-type structure as the same as MgB2. The superconducting critical temperature showed a maximum of T-c = 3.48 K near x = 0.05 and monotonically decreased with x increasing up to x = 0.7 in Si substitution. The variation of T-c with Si concentration is related to the electron-phonon coupling constant X, which was calculated by use of the McMillan's equation. The variation of lambda also exhibited a maximum near x = 0.05, and it monotonically decreased with x increasing up to x = 0.7 in Si substitution.