  We investigate a simple 5D extension of the Minimal Supersymmetric (SUSY)
Standard Model (SM) that is combined with the bulk matter Randall-Sundrum (RS)
model, which gives a natural explanation the Yukawa coupling hierarchy. In this
model, matter and gauge superfields reside in the 5D bulk while a SUSY breaking
sector and the Higgs doublet superfields are localized on the infrared brane.
The Yukawa coupling hierarchy in SM can be naturally explained through the
wavefunction localization of the matter superfields. While sparticles obtain
their flavor-blind soft SUSY breaking masses dominantly from the
gaugino-mediated SUSY breaking, flavor-violating soft terms arise through the
gravity-mediated SUSY breaking which are controlled by the wavefunction
localization of the matter superfields. This structure of the model allows us
to predict the sparticle mass spectrum including flavor-violating terms. We
first explicitly determine the 5D disposition of matter superfields from the
low energy experimental data on SM fermion masses, CKM matrix and the neutrino
oscillation parameters. Then, we calculate particle mass spectra and estimate
the effects of the flavor-violating soft terms, which should be compared with
the current experimental constraints. With gravitino being the lightest
sparticle (LSP), the next-to-LSP, which is long-lived, is predicted most likely
to be either singlet smuon-like or selectron-like. The model can be tested at
collider experiments through flavor-violating processes involving sparticles.
The flavor structure among sparticle, once observed, gives us a clue to deep
understanding of the origin of Yukawa coupling hierarchy.
