Biomedical Engineering Reference
In-Depth Information
Figure 15.5
(a) Sketch of the optical set up. Two long working distance
objectives (50
×
)in
∼
100
◦
geometry supply the laser excitation to the
grating and the collection of the scattered light to a CCD detector. (b, c) HV
and HH geometries reveal the HE
1
mode. (d-f) VU, VV, and VH geometries
identifying the TM
0
mode.
expected a SPP coupling through the grating which substantially
maintain the polarization characteristic of the source propagating
downtothestructureasaHE
1
mode.Thisisconfirmedbyimagesof
Fig. 15.5b,c that identify a substantially linearly polarized mode.
15.2.6
Conclusions
We projected and realized an e
cient plasmonic device capable
of collect and subsequently deliver energy at nanoscale, either
as radiated photons or as emitted (through a Schottky barrier)
energetic electrons. We provided the optical and electric response
characterizationmethodsleadingtodifferentpracticalapplications.
It's worthwhile mention that this plasmonic approach to AFM
spectroscopy introduces a quite new tool for chemio-physical
semiconductivedevices investigation.
Furthermore, the mapping of the photoelectric signal recorded
with a spatial resolution close to the tip contact diameter could
