M. Iwami et al., Relation between the radius of tip curvature and the light emission efficiency from scanning tunneling microscope, JPN J A P 1, 39(8), 2000, pp. 4912-4913
The relation between the efficiency of scanning tunneling microscope light
emission (STM-LE) and the radius of tip curvature has been studied using si
lver tips. The emission efficiency increases with decreasing radius of tip
curvature p for p > 80 nm. This result agrees qualitatively with the predic
tion of a theory that includes the effect of electromagnetic retardation.