Page 217 - Principles and Applications of NanoMEMS Physics

206 Chapter 5

focusing a 750 nm, 5mW laser beam on a silver nanoparticle of 200 nm
diameter and 60 nm height. Bragg mirrors, see Fig. 5-11(a), consisted of five

Bragg
Bragg
Mirror
Mirror

SP Launcher
SP Launcher
(a)

SP Launcher
SP Launcher
(b)
Figure 5-11. Sketches of SP-based devices. (a) Bragg mirror. (b) Beam interferometer. The
circle represents the focus of the impinging laser. The dashed arrows represent propagating
SPs.
°
lines of gold 140 nm diameter, 70 nm height gold inclined at a 30 angle
with respect to the nanowire used for launching the SPs. Within each line,
the center-to-center particle distance was 220 nm and, to fulfill the Bragg
condition at an SPP wavelength of 610 nm, the inter-line distance was 350
nm. A reflection coefficient of ~90% was estimated. Since the transmitted
intensity was found to be negligible, this was taken to mean that 10% of the
SP intensity was converted to light. A beam interferometer was configured