  Low energy properties of the metallic state of the 2-dimensional tJ model are
presented at various densities and temperatures for second neighbor hopping t',
with signs that are negative or positive corresponding to hole or electron
doping. The calculation employs a closed set of equations for the Greens
functions obtained from the extremely correlated Fermi liquid theory. These
equations, when used in $d=\infty$ reproduce most of the known low energies
features of the $U=\infty$ Hubbard model. In 2-dimensions we are able to study
the variations due to the superexchange J. The resulting Dyson self energy is
found to be momentum dependent as expected. The density and temperature
dependent quasiparticle weight, decay rate and the peak spectral heights over
the Brillouin zone are calculated. We also calculate the resistivity, Hall
conductivity and cotangent of the Hall angle in experimentally relevant units.
These display significant thermal sensitivity for density n >~ 0.8, signifying
an effective Fermi-liquid temperature scale which is two or three orders of
magnitude below the bare bandwidth. Flipping the sign of the hopping t', i.e.
studying hole versus electron doping, is found to induce a change in curvature
of the temperature dependent resistivity from convex to concave at low
temperatures. Our results provide a natural route for understanding the
observed difference in the temperature dependent resistivity of strongly
correlated electron-doped and hole-doped matter.
