Abstract

Light emitted from nominally smooth and statistically rough aluminum—aluminum oxide—gold tunnel junctions bears comparison in two main respects. First, for both types of junction the spectral composition is broadly similar, displaying a substantially reduced intensity for photon energies greater than ~2.5 eV. However, at all energies in the spectral range examined (1.8–3.5 eV) the emission from the smooth junctions is at least a factor of 10 less intense than that from rough junctions. These observations are consistent with the idea that the bulk of the output (i.e., the unpolarized component) across the entire spectral range is due to the roughness-induced scattering of a surface plasmon polariton mode.

© 1987 Optical Society of America