Figure 1From: Plasmonic lens focused longitudinal field excitation for tip-enhanced Raman spectroscopySchematics of PL structure consisting of a couple of semi-annular slits. In the xy plane (a) and in the xz plane (b), R l = 1.55 μm, R r =1.25 μm, w = 100 nm, and h = 150 nm. Topographic image of the PL detected with an atomic force microscopy (c).Back to article page