  We report the influence of external pressure (P= up to 8 GPa) on the
temperature dependence of electrical resistivity of a Yb-based Kondo lattice,
YbPd2Si2, which does not undergo magnetic ordering under ambient pressure
condition. There are qualitative changes in the temperature dependence of
electrical resistivity due to the application of external pressure. While the
resistivity is found to vary quadratically below 15 K (down to 45 mK)
characteristic of Fermi-liquids, a drop is observed below 0.5 K for P= 1 GPa.
Since the resistance values do not attain zero, we are attempted to attribute
this drop to magnetic ordering, rather than to superconductivity. The
temperature at which this fall occurs goes through a peak as a function of P (8
K for2 GPa and about 5 K at higher pressures). mimicking Doniach's magnetic
phase diagram. We conclude that this is one of the few Yb-based stoichiometric
materials, in which one can travers from valence fluctuation to magnetic
ordering by the application of external pressure.
