Download Third-Harmonic Generation in Photonic Crystals

“Lighting the Way to
Technology through Innovation”
The Institute for Lasers, Photonics and Biophotonics
University at Buffalo
Emerging Opportunities
In New Directions of Photonics:
Nanophotonics and Biophotonics
P.N.Prasad
www.biophotonics.buffalo.edu
NANOPHOTONICS
Nanoscale Optical Interaction and Dynamics:
Nonradiative Processes for Photonic Functions/Dynamics <10 nm
Optically Induced Photonics Functions/Dynamics sub wavelengths
Manifestations:
 Size Dependent Optical Transitions
 Novel Optical Resonances
 Nano-control of Excitations Dynamics
 Manipulation of Light Propagation
 Nanoscopic Field Enhancement
NANOPHOTONICS
Paras N. Prasad
(John Wiley & Sons, April 2004)
SUMMARY OF CONTENTS
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
Introduction
Foundations for Nanophotonics
Near Field Interaction and Microscopy
Quantum Confined Materials
Plasmonics
Nanocontrol of Excitation Dynamics
Processing and Characterization of Nanomaterials
Nanostructured Molecular Architectures
Nanocomposites
Photonic Crystals
Nanolithography
Biomaterials for Nanophotonics
Nanophotonics for Biotechnology and Nanomedicine
The Market Place for Nanophotonics
Nanocomposites for Broad Band and
Efficient Photovoltaic, Solar Cells
Hole transporting polymer + Inorganic semiconductor
quantum dots
Features:
• In corporation of quantum dots to produce a direct junction
between the polymer and the quantum dots.
• Efficient photosensitization over a broad wavelength covering
from UV to IR by choice of the size and type of inorganic
semiconductor nanocrystals ... efficient solar harvesting.
• Enhanced carrier mobility for improved collection efficiency.
InP, and InP/II-VI-Core-Shell Nanocrystals
Quantum Engineering of InP/II-VI Core-shell nanocrystals
II-VI
II-VI
InP
InP
Core/Shell nanocrystal
II-VI
Core/Buffer/Shell nanocrystal
(also magnetic nanocrystals)
InP/CdS
InP/CdSe
Etched InP
InP/ZnS
Etched InP nanocrystals and CoreShell nanocrystals (302nm excitation)
Size Tuning of Photosensitization in IR
using PbSe Quantum Dots
Photogeneration Quantum
Efficiency of PbSe Quantum Dots:
PVK nanocomposites at 1.55µm
(Dispersion in tetrachloroethylene)
2.0
-2
4.0x10
Photogeneration QE,  [%]
Absorbance [a.u.]
1.5
1.0
0.5
-2
3.0x10
-2
2.0x10
-2
1.0x10
0.0
0.0
600
800
1000
1200
1400
1600
Wavelength [nm]
1800
2000
2200
0
10
20
30
Applied Field, E0 [V/m]
40
50
Multifunctionality in Photorefractivity:
Photoconductivity + Electro-Optic Effect
+++
---
+++
---
+++
- - - Photogeneration of charge carriers
z
+++
---
+++
---

---
+++
---
Transport of holes under the influence of external
electric field
z E
---
+++
p/2
LG
+++
Trapping of Space charge
z
Electro-optic Index modulation
z
Photorefractive nanocomposite containing polymerdispersed Liquid Crystal and Quantum Dots
~ 200 nm Liquid Crystal Nanodroplets
ne
np
~ 10 nm Quantum Dots
no
PMMA:ECZ:
LiquidCrystal:CdS
Photorefractive inorganic-organic polymer-dispersed
liquid crystal nano-composite photosensitized with
cadmium sulfide quantum dots
80
Diffraction Efficiency, h [%]
70
60
PMMA:TL202:ECZ:CdS
42:40:16:2 wt.%.
50
40
30
l = 514.5 nm
Q-CdS diam. < 1.4 nm
20
10
0
0
20
40
60
80
100
Electric Field, E [V/m]
Winiarz and Prasad J., Opt. Lett. (in press)
Photorefractivity for Correction of Beam Distortion
Unaberrated
Aberrated
Corrected
Demonstration of the ability of the PMMA:ECZ:TL202:Q-CdS composite to correct a
severely aberrated image under static conditions.
Photonic crystals – A novel periodic photonic structure
0.36
band 2
0.32
0.28
Frequency
0.24
Photonic Band Gap
0.20
0.16
0.12
0.08
band 1
0.04
0.00
-3
-2
-1
0
1
2
3
Wavevector
Simple band picture for a photonic crystal
100
100
80
80
Reflectance [%]
Transmittance [%]
3D colloidal crystal
60
40
60
40
20
20
0
440 460 480 500 520 540 560 580 600
0
450
Wavelength [nm]
Transmission and reflection spectra
500
550
600
650
Wavelength [nm]
700
750
Novel Manifestations in Photonic Crystals
1.3
1.2
1.0
0.9
0.8
0.7
0.6
0.5
0.4
Field enhancement
0.3
- Low threshold lasing
- Enhanced nonlinear optical effects
0.2
0.1
0.0
X
U
L
G
X
W
K
Wavevector [p/a]
Complex band structure
1.50
Effective refractive index
Normalized frequency
1.1
1.48
1.46
1.44
1.42
0.1
520nm
1560nm
0.2
0.3
0.4
0.5
0.6
0.7
Normalized frequency
Superprism effect
- Negative refraction
- Large angle deflection
- Ultradiffraction
Anomalous refractive index dispersion
- Control of light propogation
- Phase-matching for harmonic generation
- Self-collimation
Third-Harmonic Generation in Photonic Crystals
40 nm off
I  500 GW/cm 2
2500
1.0
2000
0.8
1500
0.6
1000
0.4
500
0.2
0
400
450
500
550
Transmittance
THG Intensity [a.u.]
Third-Harmonic Generation in Photonic Crystals
0.0
600
Wavelength[nm]
Third-harmonic generation in two
polystyrene PCs (d=200 & 230 nm).
The intensity of THG from the 1-D
photonic crystal as a function of the
pump wavelength.
P. Markowicz at. al., Phys. Rev. Lett. - in press.
Light Driven Nanoparticle Alignment
Use of holographic (laser) photopolymerization to induce movement and sequester
nanoparticles into defined 3-dimensional patterns
Holographic Illumination
Intensity interference
pattern
Sub-micron periods
(50-800 nm)
Functional nanoparticles
in reactive mixture
Spatially defined chemical reactivity
150 nm
Advantages: Large Scale Area, Various Geometries, Simple, and One Step Processing
Electrically Switchable Photonic Crystal
Holographic polymer-dispersed liquid crystal grating.
1.0
0.9
0.8
Intensity [a. u.]
TH Intensity [a. u.]
THG
U=0V
0.8
0.6
0.4
U=160V
0.2
0.0
480
0.7
0.6
0.5
0.4
Transmission
0.3
500
520
540
560
580
600
Wavelength[nm]
The intensity of THG from the 1-D photonic
crystal as a function of the applied voltage.
480
500
520
540
560
580
600
Wavelength[nm]
The transmission spectrum of the
crystal & the third-harmonic signal.
In collaboration with AFRL, Dayton
Two-photon Lithography using femtosecond pulses
Photonic Crystal Defect Engineering: Optical Circuitry
Two-photon fluorescence
P. Crystal
Objective
Infiltration with Resin
& 2-photon
Lithography
Grating
One-photon fluorescence
P. Crystal &
Linear Defects
1x2 Beam Splitter
(5microns below surface)
Laser Tweezers for micro- and nano- manipulation
and surface adhesion
Letters composed in Liquid Crystal
Multiple trapping in water by one beam
Measurement of colloidal forces and defect line tension and in liquid crystal
In collaboration with Smalyukh and Lavrentovich, ILC, Kent State University
Introduction to Biophotonics
Paras N. Prasad
(John Wiley & Sons, 2003)
SUMMARY OF CONTENTS
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
Introduction
Fundamentals of Light and Matter
Basics of Biology
Fundamentals of Light-Matter Interactions
Principles of Lasers, Current Laser Technology, and Nonlinear Optics
Photobiology
Bioimaging: Principles and Techniques
Bioimaging: Applications
Biosensors
Microarray Technology for Genomics and Proteomics
Flow Cytometry
Light-Activated Therapy: Photodynamic Therapy
Tissue Engineering with Light
Laser Tweezers and Laser Scissors
Nanotechnology for Biophotonics: Bionanophotonics
Biomaterials for Photonics
Drug tracking using TPLSM
Doxorubicin
: Chemotherapy drug
LHRH Peptide
: Targeting agent.
C625
: Two-photon Chromophore
l = 800nm
Avg. Power < 15mW
=~ 90 fs
f =82 MHz
TPLSM images of MCF-7 cells showing the intake of
drug into cell over a time period of 50 minutes.
Confocal images of MCF 7 cells. The arrows
indicate The location where the spectra were taken.
Cytoplasm
Nucleus
Membrane
Spectra profiles of AC&LHTPR treated MCF-7 cell
(inside the Nucleus, Cytoplasm and on the Membrane)
Localized spectroscopy was used
to identify the localization of a
chemotherapeutic drug and and
one of its component, the carrier
protein, inside human cancer
cells.
AC
LHTPR
The ratio between the two
emission at ~490nm (From
AN152:C625) and the Emission
at ~590 (From LHRH:TPR) was
studied in different cell lines as
well as in different parts of a cell
to understand the roll of LHRH
in carrying the drug into the cells.
Excitation Source: Ti:Sapphire laser tuned to a center wavelength of 800nm.
FRAP : A technique to monitor protien Dynamics in Cells
FGFR1-eGFP
Pre -Bleach
Post -Bleach
Nucleus
t ½ (s)
Nuclear Membrane
53.78
95% Confidence
Recovery
Plasma Membrane
76.52
50.82 to
37.63
71.70 to 82.03
35.55 to 39.97
57.10
40
Fluorescence Recovery (%)
Nucleus
NM
30
PM
20
10
0
0
100
200
Time (s)
300
400