Future electronics: Photonics and plasmonics at the nanoscale
Robert Magnusson Texas Instruments Distinguished University Chair in Nanoelectronics Professor of Electrical Engineering Department of Electrical Engineering University of Texas-Arlington Arlington, Texas 76019 [email protected] http://leakymoderesonance.com/
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Applied Power Electronics Conference Fort Worth, Texas March 16 – 20, 2014
Scope
Plasmonics: Surface plasmons are coherent electron oscillations at the interface between two materials where the real part of the dielectric function changes sign across the interface.
Nanoplasmonics: Plasmonics in nanoscale systems. Photonics: Technology concerned with the properties and transmission of
photons, for example in fiber optics, waveguides, and lasers. Nanophotonics the study of the behavior of light on a nanometer scale.
Engineering the interaction of light with particles or substances at deeply subwavelength scales.
Silicon photonics: CMOS! Focus: Nanophotonic and nanoplasmonic periodic devices.
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Surface plasmons on dielectric-metal boundaries
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Nanoplasmonics
Metal coupler example
Jesse Lu, Csaba Petre, Eli Yablonovitch, and Josh Conway, “Numerical optimization of a grating coupler for the efficient excitation of surface plasmons at an Ag–SiO2 interface,” J. Opt. Soc. Am. B/Vol. 24, No. 9/September 2007
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Undergrad plasmonics: SPR sensor experiment
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SP-highlights Surface plasmon: EM field charge-density oscillation at the interface
between a conductor and a dielectric SP: AC current at optical frequency Metallic structures: Concentrate/focus/guide light via SPs SP localization: Better than with dielectric optical means Efficient coupling/manipulation: Under intensive research Plasmonics: An electronics/photonics interface
Our interest:
– Interaction/generation of plasmonic states employing leaky-mode resonance effects – Fundamental plasmonic research in periodic nanostructures – Theory and experiment in all cases
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Collective excitation of the free electrons in a metal Can be excited by light: photon-electron coupling (polariton)=SPP Thin metal films or metal nanoparticles Bound to the interface (exponentially decaying along the normal) Longitudinal surface wave in metal films Can be highly confined in nanostructures (localized plasmon) Propagates along the interface: few µm to several mm (long range plasmon)
Surface plasmons-key properties
Note: SP is a TM wave!
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Model Device: Canonical periodic element Tranmission and modal properties
Fixed Parameters εmetal = -5, F = 0.05
incE
incH
Λ
FΛ
metalε
d
air air
Yiwu Ding, Jaewoong Yoon, Muhammad H. Javed, Seok Ho Song, and Robert Magnusson, “Mapping surface-plasmon polaritons and cavity modes in extraordinary optical transmission,” IEEE Photonics Journal, vol. 3, no. 3, pp. 364–374, June 2011. 8
Device possesses mixed cavity-modal (CM) and surface-plasmon states (SPP) => EOT=extraordinary transmission
Parametric Map of transmission function EOT
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.00.0
0.2
0.4
0.6
0.8
1.0
Λ/λ
d/λ
TM0
mixed SPP/CM region d/Λ=0.086 0.2 0.37 0.46 0.72
cavity mode (CM) region
TM1 TM2
TM3 TM4 TM5 TM6
TM7
even mode odd mode higher order SPP
pure SPP region
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0.2 0.3 0.4 0.5 0.6 0.7 0.80.5
0.6
0.7
0.8
0.9
1.0
Λ/λ
d/λ
Mixed SPP-CM Region
magnetic field patterns on TM2 curve
• Gradual increase of surface field enhancement associated with SPP excitation • Abrupt change in Fabry-Perot condition • Missing resonance peaks
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Leaky modes and plasmons:
Hybrid resonance elements
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0.5 0.6 0.7 0.8 0.9 1.00.0
0.2
0.4
0.6
0.8
1.0
d=0 d=100nm d=900nm
R 0
wavelength (µm)
Au
dielectric (n = 1.6)
I R0
F=0.4 (fixed)
TM(a) (b)
(c)
air
d = 100 nm, λ = 710.5 nm
(d)
d = 900 nm, λ = 618.5 nm0
5
10
15
20
0
5
10
15
d
FΛ Λ
Robert Magnusson, Halldor Svavarsson, Jae Woong Yoon, Mehrdad Shokooh-Saremi, and Seok-Ho Song, “Experimental observation of leaky modes and plasmons in a hybrid resonance element,” Applied Physics Letters, vol. 100, no. 9, pp. 091106-1–091106-3, February 29, 2012.
Measured spectra-computed fields
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500 nmsilicon
AuPR
0.0
0.2
0.4
0.6
0.8
1.0
R 0
TM
0.60 0.65 0.70 0.75 0.80 0.85 0.900.00.2
0.40.60.81.0
wavelength (µm)
TE
SPP(799 nm)
TM1(669 nm)
calculated
measured
calculated
measuredTE0
(725 nm)
0
10
5
0
16
8
0
20
10
TM1
air PR
AuSi
(a)
(b)
(c) TE0
SPP
Appl. Phys. Lett. 2012 Parameters: Λ = 653 nm, dPR = 560 nm, dAu = 80 nm, n = 1.6, and F = 0.35.
Silicon photonics: Intel vision
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Motivation for silicon photonics Limits of microelectronics evolution Optical communication evolution Interconnection bottlenecks Compact, low loss, EMI properties SiPhot=new technology platform Low cost High performance
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15 Reference: Silicon Photonics–PhD course prepared within FP7-224312 Helios project
Huge opportunities for innovation!
16 Reference: Silicon Photonics–PhD course prepared within FP7-224312 Helios project
Basic resonance interactions Excitation of a leaky eigenmode in 1D periodic layers
Higher-order diffraction regime Zero-order diffraction regime
Properties of 2D nanopatterns similar in principle
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Experimental spectra
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1460 1480 1500 1520 1540 1560 15800.0
0.2
0.4
0.6
0.8
1.0
Theory Experiment
R
efle
ctan
ce
Wavelength (nm)
1450 1500 1550 1600 1650 1700 17500.0
0.2
0.4
0.6
0.8
1.0
TE TM
Tran
smitt
ance
Wavelength (nm)
0.78 0.79 0.8 0.81 0.82 0.83 0.84 0.85 0.860
0.2
0.4
0.6
0.8
1
Wavelength(µm)
Tra
nsm
ittan
ce
SimulationExperiment
1.4 1.45 1.5 1.55 1.6 1.65
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
λ (µm)
Tran
smitt
ance
SimulatedMeasured
• Interesting physics/properties
• Complex, interacting resonant leaky modes
• 1D or 2D periodic layers
• Applicable to dielectrics, semiconductors, metals
• Applicable to photonic, THz, microwave spectral regions
• Remaining challenges in analysis
• Remaining challenges in fabrication
• Many potential application fields
• Applications emerging ~Biosensors
• Favorable area for R&D&A
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Guided-mode resonance nanophotonics: Innovation/applications platform
Unknown unknowns
Known knowns
R. Magnusson et al., “Extraordinary capabilities of optical devices incorporating guided-mode resonance gratings,” Optoelectronic Devices and Materials (OPTO), Photonic Integration: Integrated Optics: Devices, Materials, and Technologies XVIII, SPIE Photonics West 2014, San Francisco, California, February 1–6, 2014.
Guided-mode resonance technology: Application summary
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Frequency selective elements - Narrowband bandstop/bandpass filters (∆λ~sub nm) - Wavelength division multiplexing (WDM) - Ultra high-Q thin-film resonators - Laser resonator frequency selective mirrors Biochemical sensors - Spectroscopic biosensors - Chemical and environmental sensors - Multiparametric biosensors (biolayer thickness, refractive index, and background in a single
measurement) Wideband lossless mirrors - Wideband bandstop/bandpass filters (∆λ~100’s nm) - Mirrors for vertical-cavity lasers - Omnidirectional reflectors Polarization control elements - Polarization independent reflection/transmission elements for both 1D and 2D periodicity - Narrow or wideband polarizers - Non-Brewster polarizing laser mirrors - Polarization control including wave plates
Guided-mode resonance technology: Application summary
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Tunable elements - Tunable filters, EO modulators, and switches - Liquid-crystal integrated tunable devices - Laser cavity tuning elements - MEMS-tunable display pixels and filters - Thermally tuned silicon filters Security devices - Resonant Raman templates - Compact non-dispersive spectroscopy Thin-film light absorbers - Absorbance-enhanced solar cells - Omnidirectional, wideband, polarization-independent absorbers - GMR coherent perfect absorbers Photonic metasurfaces - Wavefront-shaping elements including focusing reflectors Dispersive elements - Slow-light/dispersion elements Hybrid resonant elements - Leaky-mode nanoplasmonics - Hybrid plasmonic/modal resonance sensors - Rayleigh reflectors with sharp angular cutoff - Rayleigh-anomaly based GMR transmission filters
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Wideband resonant reflectors
T0
SiO2
air
Ge
FΛ Λ
dg dh
x
y z
R0
2.0 2.2 2.4 2.6 2.8 3.0 3.20.0
0.2
0.4
0.6
0.8
1.0
R0
zero
-ord
er e
fficie
ncy
wavelength (µm)
T0
Model and reflectance/transmittance spectra of a GMR mirror applying a partially etched Ge layer. Input light is in a TM polarization state.
BW~900 nm
R. Magnusson et al., “Extraordinary capabilities of optical devices incorporating guided-mode resonance gratings,” Optoelectronic Devices and Materials (OPTO), Photonic Integration: Integrated Optics: Devices, Materials, and Technologies XVIII, SPIE Photonics West 2014, San Francisco, California, February 1–6, 2014.
Color filter array: Design
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Period-tuned resonance wavelengths enabling RGB color filters.
Parameters: n = 2.02, F = 0.5, dg = 55 nm, and dh = 110 nm.
Designed and optimized with RCWA
Mohammad J. Uddin and Robert Magnusson, “Highly efficient color filter array using resonant Si3N4 gratings,” Optics Express, vol. 21, no. 10, pp. 12495–12506, May 20, 2013.
Results: Spectral measurements
Device Parameters: dg = ≈ 60 nm, dh ≈ 105 nm, F = 0.46.
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High experimental efficiency (> 95%) with low crosstalk
Mohammad J. Uddin and Robert Magnusson, “Highly efficient color filter array using resonant Si3N4 gratings,” Optics Express, vol. 21, no. 10, pp. 12495–12506, May 20, 2013.
Label-free Microarrays Based on Guided-mode Resonance Technology
ResonantSensors.com 817-735-0634 [email protected]
Products Features
Fully automated benchtop reader Optical resonance with real-time data
96-well and 384-well disposable label-free microarray plates
Cell-based and biochemical assays
Pre-sensitized kits: standard and custom
Dual-resonance detection enables two data points for every measurement
Comprehensive assay support for transition to label-free
Multiplexing capability
Conclusions • Nanoplasmonics
– Light on metals-compact devices – Loss/gain compromise – Rapid R&D
• Silicon photonics – CMOS infrastructure – Integrated electronics/photonics chips – Commercial now – Under intense development
• Nanophotonics – Device development opportunities – Opportunities in entrepreneurship/innovation
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