Space charge limited photoelectric emission in a plane parallel electrode geometry

The problem of space charge limited photoelectric emission in a plane parallel electrode geometry is considered for an emitting electrode composed of material with a constant optical absorption coefficient and a classical step surface barrier. Poisson's equation is solved for the limit of zero cathode temperature and this solution shown to be applicable to the general case if the ratio of the collection current J to the saturation current J s satisfies ( pi 2 /3)(kT/h( nu - nu 0 )) 2 <