Temperature dependence of the resistivity of a dilute two-dimensional electron system in high parallel magnetic field

We report measurements of the resistance of silicon metal-oxide-semiconductor field-effect transistors as a function of temperature in high parallel magnetic fields where the two-dimensional system of electrons has been shown to be fully spin polarized. In a field of 10.8 T, insulating behavior is found for densities up to $n_s\approx 1.35\times {10}^{11}{\mathrm{cm}}^{-2}\approx {1.5n}_c;$ above this density the resistance is a very weak function of temperature, varying less than 10% between $0.25$ and $1.90$ K. At low densities $\overrightarrow{\rho }\infty$ more rapidly as the temperature is reduced than in zero field and the magnetoresistance $\Delta \rho /\rho$ diverges as $\overrightarrow{T}0$.