Electron-hole Coulomb interaction
= Electron-hole Coulomb interaction
{title2=$V(r)=-e^2/(4\pi\epsilon_0\epsilon_r r)$}
The attractive electrostatic interaction between an <electron> and an <electron hole>. In a screened effective-mass approximation its potential has the displayed form. It can bind an <exciton> and reduce its optical excitation energy below the corresponding unbound-pair threshold.