Quantum capacitance
= Quantum capacitance
{title2=$C_Q=e^2\partial N/\partial\mu$}
The electronic contribution to differential <capacitance> arising from a change of <chemical potential> as particles are added. For noninteracting <Electrons> at zero <temperature>, it is $e^2$ times the <density of states> of the whole sample at the <Fermi energy>. The <quantum capacitance of a graphene cone> gives a worked example.