{disambiguate=quantum Hall effect}
{title2=$\nu_f=n_sh/(eB)$}

= Filling factor
{synonym}

For a <two-dimensional electron gas> in a perpendicular <magnetic field> of magnitude $B>0$, the <filling factor> is the <Electron> number per unit <area> $n_s$ divided by the orbital degeneracy per unit <area> $eB/h$ of one <spin> branch of a <Landau level>. Here $e$ is the positive <elementary charge> and $h$ the <Planck constant>. The nominal <filling factor> varies continuously with $n_s/B$; it need not be an integer.


 Filling factor (quantum Hall effect) (source code)