Hall coefficient of a dilute two-dimensional electron system in a parallel magnetic field

Measurements in magnetic fields applied at a small angle with respect to the two-dimensional plane of the electrons of low-density silicon metal-oxide--semiconductor field-effect transistors indicate that the Hall coefficient is independent of parallel field from $H=0$ to $Hg{H}_{\mathrm{sat}},$ the field above which the longitudinal resistance saturates and the electrons have reached full spin polarization. This implies that the mobilities of the spin-up and spin-down electrons remain comparable at all magnetic fields and suggests there is strong mixing of spin-up and spin-down electron states.