Abstract
A prism coupling arrangement is used to excite surface plasmons at the surface of a thin silver aim and a photon scanning tunnelling microscope is used to detect the evanescent field above the silver surface. Excitation of the silver/ air mode of interest is performed at lambda(1) = 632 . 8 nm using a tightly focused beam, while the control of the tip is effected by exciting a counter-propagating surface plasmon field at a different wavelength. lambda(2) = 543 . 5 nm, using an unfocused beam covering a macroscopic area. Propagation of the red surface plasmon is evidenced by an exponential tail extending away from the launch site, but this feature is abruptly truncated if the surface plasmon encounters the edge of the silver film - there is no specularly reflected 'beam'. Importantly, the radiative decay of the surface mode at the film edge is observable only at larger tip-sample separations, emphasizing the importance of accessing the mesoscopic regime.
Original language | English |
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Pages (from-to) | 578-583 |
Number of pages | 6 |
Journal | Journal of Microscopy |
Volume | 194 |
Publication status | Published - 1999 |
Event | 5th International Conference on Near Field Optics and Related Techniques (NFO-5) - SHIRAHAMA, Japan Duration: 06 Dec 1998 → 10 Dec 1998 |
Keywords
- attenuated total reflection
- photon scanning tunnelling microscope
- scattering
- surface plasmon polariton
- SCATTERING
- INTERFERENCE
- ROUGHNESS
- FIELD