Y. Uehara et al., Tip shape dependence of the light emission efficiency for the scanning tunneling microscope, APPL PHYS L, 79(11), 2001, pp. 1718-1720
We have investigated the relation between the scanning-tunneling-microscope
(STM) tip shape and the efficiency of STM light emission. The light intens
ity radiated by a current source placed in the tip-sample gap of the STM wa
s calculated for various shapes of the tip using the finite differential ti
me domain method. We found that the highest emission efficiency is obtained
for the pyramidal tip with the flat top of 4 nm width and the apex angle o
f 90 degreesC. (C) 2001 American Institute of Physics.