Download Simulation Structure

Beam manipulation via
plasmonic structure
Kwang Hee, Lee
2010. 5. 19
Photonic Systems Laboratory
Contents
• Introduction of surface plasmon polariton(SPP)
• Extraordinary transmission(EOT)
• Effect factors of transmission
• Exit patterning
• Summary
Photonic Systems Lab
School of EECS, S.N.U.
What is the SPP?
1
Dielectric
z
e
x
++ --
2
Metal
for
Photonic Systems Lab
++
 1 z
1  2

0
1  2
- - ++ ++
e
 2z
Evanescent modes
1   2  0
School of EECS, S.N.U.
SPP at a single interface
Photonic Systems Lab
School of EECS, S.N.U.
Where can SPP be used?
Integrated electro-photonics,
will remove the crosstalk and Ohmic loss of Electronics
meanwhile retaining the nano-features of Electronics
Photonic Systems Lab
School of EECS, S.N.U.
EOT
• Extraordinary Transmission (EOT)
Sub-wavelength hole arrays : peak at above a0
 contribution of surface modes
Due to grating coupling at regular, periodic lattice
Phase matching condition
Ebbesen, T. W., Lezec, H. J, Ghaemi, H. F., Thio, T., and Wolff, P. A. “Extraordinary optical transmission through sub-wavelength hole
arrays.” Nature, 931:667–669. 1998.
Photonic Systems Lab
School of EECS, S.N.U.
EOT
• Extraordinary Transmission (EOT)
EOT occurs at another structures : Bull’s eye, square dimple
array, slit array
Thio, Tineke, Pellerin, K. M., Linke, R. A., Lezec, H. J., and Ebbesen, T. W. “Enhanced light transmission through a single subwavelength
aperture.” Opt. Lett., 26(24):1972–1974. 2001.
Porto, J. A., Garcia-Vidal, F. J., and Pendry, J. B. “Transmission resonances on metallic gratings with very narrow slits.” Phys. Rev. Lett.,
83(14):2845–2848. 1999.
Photonic Systems Lab
School of EECS, S.N.U.
Effect factors of transmission
• Factor for Surface Plasmon Polaritons (SPP)
– Flim thickness : T saturation for small thickness (order of
skin depth)
– Hole width : T increases and the peaks broaden for
increasing hole width
Degiron, A., Lezec, H. J., Barnes,W. L., and Ebbesen, T.W. “Effects of hole depth on enhanced light transmission through subwavelength
hole arrays.” Appl. Phys. Lett., 81(23):4327–4329. 2002.
van der Molen, K. L., Segerink, F. B., van Hulst, N. F., and Kuipers, L. “Influence of hole size on the extraordinary transmission through
subwavelength hole arrays.” Appl. Phys. Lett., 85(19):4316–4318. 2004.
Photonic Systems Lab
School of EECS, S.N.U.
Effect factors of transmission
• Factor for Surface Plasmon Polaritons (SPP)
– Coupled cavity modes in the grooves
• h : about frequency
• d : about in-phase re-emmision
– Exit side grooves don’t influence T
García-Vidal, F. J., Lezec, H. J., Ebbesen, T. W., and Martín-Moreno, L. “Multiple paths to enhance optical transmission through
a single subwavelength slit.” Phys. Rev. Lett., 90(21):213901. 2003.
Photonic Systems Lab
School of EECS, S.N.U.
Effect factors of transmission
• Localized Surface Plasmons (LSP)
In contrast to PEC case, the maximum in the transmission of real metal near 580 nm can
be associated with the excitation of a localized surface plasmon.
the nanohole excitation decays not only into scattered light, but into surface plasmon
polaritons.
Chang et al.,“Surface plasmon generation and light transmission by isolated nanoholes and arrays of nanoholes in thin metal films”,
Opt. Express, Vol.13, No.8, 3150, 2005.
Photonic Systems Lab
School of EECS, S.N.U.
Effect factors of transmission
• Localized Surface Plasmons (LSP)
Charges accumulate at the edges with a length scale
of one wavelength. This increasing charge density
enhances the electric field.
The electric field is proportional to the charging
time or equivalently 1/f.
Seo et al.,“Terahertz field enhancement by a metallic nano slit operating beyond the skin-depth limit”, Nature Photonics, Vol.3,No.3,152-156, 2009.
Photonic Systems Lab
School of EECS, S.N.U.
Effect factors of transmission
• Waveguide resonance
Normalized-to-area transmittance at resonance is proportional to
the aspect ratio, and to the dielectric constant inside the hole.
A transmission peak develops at approximately λc=2ay, with increasing
maximum transmittance and decreasing linewidth as ay/ax increases.
F.J.Garcia-Vidal et al., “Transmission of Light through a Single Rectangular Hole” , PRL, 95, 103901, 2005.
Photonic Systems Lab
School of EECS, S.N.U.
Exit surface patterning
• Exit surface patterning enables directional emission
Lezec, H. J., Degiron, A., Devaux, E., Linke, R. A., Martin-Moreno, L., Garcia-Vidal, F. J, and Ebbesen, T. W. “Beaming light
from a subwavelength aperture.” Science, 297:820– 822. 2002.
Photonic Systems Lab
School of EECS, S.N.U.
Exit surface patterning
• Narrow beam profile is obtained with about 10 grooves
Martín-Moreno, L., Garcia-Vidal, F. J., Lezec, H. J., Degiron, A., and Ebbesen, T. W. “Theory of highly directional emission
from a single subwavelength aperture surrounded by surface corrugations.” Phys. Rev. Lett., 90(16):167401. 2003.
Photonic Systems Lab
School of EECS, S.N.U.
Exit surface patterning
• Off-axis beaming with asymmetric surface gratings
Seyoon Kim, Hwi Kim, Yongjun Lim, and Byoungho Lee, “Off-axis directional beaming of optical field diffracted by a single
subwavelength metal slit with asymmetric dielectric surface gratings” Applied Physics Letters 90, 051113, 2007
Photonic Systems Lab
School of EECS, S.N.U.
Applications
• Near-field optical probe
(conical geometry)
• Micro-fluidic detector
ε=1.8978
ε=2.2506
Drezet et al., “Extension of Bethe’s diffraction model to conical geometry” ,Europhys. Lett., 54(6), pp. 736-740, 2001.
Bravo-Abad et al., “Transmission properties of a single metallic slit” ,Physical Review E, 69, 026601, 2004.
Photonic Systems Lab
School of EECS, S.N.U.
Applications
• Optical switching using nonlinear material
d=0.75, a=0.05, h=0.45 um
The transmission spectra differ
for increasing and decreasing
fluxes.
 Optical bistability
Porto et al., “Optical bistability in subwavelength slit apertures containing nonlinear media”, Phys. Rev. B, 70, 081402, 2004.
Photonic Systems Lab
School of EECS, S.N.U.
Summary
• SPP has a great possibility to integrate electronics and
photonics
• Extraordinary transmission is generated from SPP
which is influenced by geometrical parameters.
• Transmission is also influenced by LSP and waveguide
resonance.
• With exit surface patterning, directional emmision and
off-axis beaming can be possible.
• EOT is applicable to various optical devices such as
switch, probe and so on.
Photonic Systems Lab
School of EECS, S.N.U.