Theory of inverse photoemission

Abstract

Electrons in the range 0-20 eV accelerated by the potential inside a surface emit photons over a range of frequencies, with a probability related by time reversal to the excitation of an electron in angle resolved photoemission. Theory indicates that the yield is high enough to make the experiments much simpler than photoemission, providing a more valuable probe of unoccupied electron states than any available so far. Particularly interesting is the possibility of using the new spin polarised electron sources to study magnetism with the inverse photoemission (IPE) technique.