  Within the t-J model, the charge transport and spin response of the doped
bilayer triangular antiferromagnet are studied by considering the bilayer
interaction. Although the bilayer interaction leads to the band splitting in
the electronic structure, the qualitative behaviors of the physical properties
are the same as in the single layer case. The conductivity spectrum shows the
low-energy peak and unusual midinfrared band, the temperature dependent
resistivity is characterized by the nonlinearity metallic-like behavior in the
higher temperature range, and the deviation from the metallic-like behavior in
the lower temperature range, and the commensurate neutron scattering peak near
the half-filling is split into six incommensurate peaks in the underdoped
regime, with the incommensurability increases with the hole concentration at
lower dopings, and saturates at higher dopings.
