Transcript Photonic Crystals - Department of Electrical & Computer Engineering

Photonic Crystals
Photonics Research Laboratory
Department of Electrical and Computer Engineering
Old Dominion University, Norfolk, VA 23529
http://www.lions.odu.edu/~salbin/Photonics/
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Research Team
Dr. Sacharia Albin
Advisor
Dr. Shangping Guo
Post Doc Fellow
Feng Wu
Ph.D. Candidate
Khalid Ikram
Master’s Student
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Introduction
1887
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1987
1-D
2-D
periodic in
one direction
periodic in
two directions
3-D
periodic in
three directions
Periodic structures in 1D, 2D and 3D
Period comparable to wavelength (sub-microns)
Possess photonics band gaps (PBGs) which prohibit any light modes
Obey Maxwell’s equations, predicting fields accurately
Similar but fundamentally different from semiconductors
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No EMAG Radiation Inside
PBG
No electrons
No photons
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Woodpile PBG using Silicon
Micro-machining
From Sandia National Laboratory
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Photonic Micropolis
Research at MIT
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Research at ODU Photonics Lab
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1st BZ
Planar photonic devices based on 2D photonic crystals
Basic geometries: square, triangular, honeycomb, kagome
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Examples of Photonic
Devices/Applications
 Optical insulator
 Perfect dielectric mirror
 Optical filter
 Polarizer
 Super-lensing
 Negative refraction
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Defects in PBG
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Point defects and line defects
High Q filter
Zero-threshold cavity
Resonance center for controlled energy transfer
Linear waveguiding & bending
Ideal integrated devices
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PBG Defect Laser
PBG provides: High Q cavity + ASE suppression,
leading to micro sized, zero-threshold laser.
From UCLA
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Example of High Q filter
Resonant cavity: high Q filter ~10,000, resonant frequency, Q
and energy pattern can be designed.
S. Guo, S. Albin, “Numerical techniques for excitation and analysis of defect
modes in photonic crystals”, Opt. Express 11, 1080-1089 (2003)
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Example of High Q filter
Possible high Q filters in a 2D square lattice, useful for many
devices: add/drop, waveguiding cross, splitter, filters, etc.
S. Guo, S. Albin, “Numerical techniques for excitation and analysis of defect
modes in photonic crystals”, Opt. Express 11, 1080-1089 (2003)
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Field Profile – Single Defect
S. Guo, S. Albin, “Numerical techniques for excitation and analysis of defect
modes in photonic crystals”, Opt. Express 11, 1080-1089 (2003)
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Example of Linear Waveguide
Linear waveguiding in arbitrary medium
S. Guo, PhD Dissertation, ODU, 2003
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Linear Waveguide : Pulse
Propagation
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Peaks in transmission spectrum, due to the cavity resonant
effect, or DBR effect (contributes to special dispersion)
Phase relation
S. Guo, PhD Dissertation, ODU, 2003
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Coupled Cavity Waveguide
S. Guo, PhD Dissertation, ODU, 2003
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Coupled Cavity Waveguide
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5 cavities, 5 peaks in the transmission
Large propagation delay in the cavity (delay line)
A setup time required
Distortion of ultra-narrow pulses
S. Guo, PhD Dissertation, ODU, 2003
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100% Transmission at Sharp
Bends
S. Guo, PhD Dissertation, ODU, 2003
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Pulse Propagation Through
Sharp Bends
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Whole band can pass
the bend with
transmission over
80%
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Peak transmission
occurs at some
frequencies due to
waveguiding and
resonant tunneling at
the bend
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S. Guo, PhD Dissertation, ODU, 2003
Add/drop channels using CCWs
S. Guo, PhD Dissertation, ODU, 2003
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CCW for add/drop Channels
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S. Guo, PhD Dissertation, ODU, 2003
Photonic Crystal Fiber
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Holey fiber with a micro-structured
cladding
Photonic band gap fiber: guiding light in
air
Bragg fiber using perfect cylindrical
dielectric mirrors (the Omniguide fiber)
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Holey Fibers
Microstructured holey fiber or PCFs,
Russel et al, Science, 2003 (Univ. Bath)
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Spatial Dispersion
S. Guo, PhD Dissertation, ODU, 2003
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Index-guiding Triangular PCF
Endless Single Mode
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Single mode from UV to infrared
Short wavelength gets a better confinement
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S. Guo, PhD Dissertation, ODU, 2003
Air-guiding PCFs
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Bragg Fiber with OmniReflector
Omnidirectional Mirrors
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Advantages
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Light guiding (at any wavelength) in air,
e.g. the CO2 laser transport for medical
applications
No need for high purity materials
Reduced nonlinear effect, zero polarization
mode dispersion, large power transfer
Asymptotic single mode propagation
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Modeling and Simulation
Methods
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Photonics lab has developed many methods
for the research on photonic crystals
Plane wave method: to calculate the band
gap structure of any photonic crystal
Time-domain: for band gap calculation
FDTD: to simulate the field dynamics in
arbitrary dielectric materials.
Fiber, PCF, Bragg fiber analysis tools
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Modeling and Simulation
Methods
 The PWM and FDTD methods
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Solved most problems in PBG field
Our free software used by hundreds of users world
wide
Dedicated discussion group
Citation by peer groups
 Fiber Analysis
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Modified plane wave methods
Galerkin method: Laguerre-Gauss, Hermite-Gauss
Compact-2D FDTD for waveguides
FDFD for arbitrary fibers
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Related Publications
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F. Wu, S. Guo, K. Ikram, S. Albin, H. Tai, B. Rogowski, “Numerical analysis of
Bragg fibers using a compact 1D finite-difference frequency-domain method,”
Opt. Comm. 249, 165-174 (2005).
S. Guo, F. Wu, S. Albin, H. Tai, B. Rogowski, “Loss and dispersion analysis of
microstructured fibers by finite-difference method,” Opt. Express 12, 3341-3352
(2004).
S. Guo, F. Wu, S. Albin, B. Rogowski, “Photonic band gap analysis using finitedifference frequency-domain method”, Opt. Express 12, 1741-1746 (2004).
S. Guo, F. Wu, K. Ikram, S. Albin, “Analysis of circular fiber with arbitrary index
profiles by Galerkin method”, Optics Letters 29,32-34 (2004).
S. Guo, S. Albin, B. Rogowski, "Comparative analysis of Bragg fibers," Opt.
Express 12, 198-207 (2004).
S. Guo, S. Albin, “Numerical techniques for excitation and analysis of defect
modes in photonic crystals”, Opt. Express 11, 1080-1089 (2003).
S. Guo, S. Albin, Simple plane wave implementation for photonic crystal
calculations, Opt. Express 11, 167 (2003).
S. Guo and S. Albin, “Transmission property and evanescent wave absorption of
cladded multimode fiber tapers”, Opt. Express 11, 215-223 (2003).
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Acknowledgments
This research is supported by NASA
Langley Research Center through
NASA-University Photonics Education
and Research Consortium (NUPERC)
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