Figure 3: Resolution enhancement by higher transverse modes.
(a) Extinction measurement of a single particle using the fundamental mode (i) and the first five higher transverse-mode families (ii)–(vi), combined to yield an enhanced-resolution mode (vii). Scale bars, 5 μm (b) Averaged section (5 rows) through the fundamental mode (red dots) and enhanced-resolution mode (blue dots) together with a fit (solid lines). (c) Achievable spatial resolution improvement, showing the ratio of the reduced (ws) and initial (w0) mode waist as a function of the maximal mode order included. (d) Extinction map of 40 nm Au NPs. (e) Enhanced-resolution map of the same area using the higher mode orders up to m+n=3. Scale bars, 10 μm
