art.yale.eduart.yale.edu/file_columns/0000/2996/krauss.pdf · Created Date: 10/30/2013 2:41:55 PM
Light generation and control in SOI Photonic...
Transcript of Light generation and control in SOI Photonic...
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.1/32
Thomas F Krauss
University of St. Andrews, School of Physics and Astronomy, St. Andrews, UK
Light generation and control in SOI Photonic crystals
Liam O'Faolain, Abdul Shakoor, Karl Welna
Christelle Monat, Bill Corcoran, Ben Eggleton, CUDOS
Matteo Galli, Dario Gerace, Simone Portalupi, Lucio Claudio Andreani, Pavia
Francesco Priolo, Giorgia Franzo, Catania
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.2/32
How grey silicon can help you generate new colours
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.3/32
1. SOI Photonic crystals
220 nm Si waveguide, airbridge or oxide clad
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.4/32
Mechanism!
a!
In the slow light regime, one can imagine the mode taking a longer route - that’s why it takes more time, and why there is more light inside the structure. !
Cavities can be understood as waveguides with their ends plugged up.!
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.5/32
Nonlinear wavelength conversion
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.6/32
Third harmonic generation
!
I" =P"A#ngneff C. Monat et al., Nature Photonics, April 2009
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.7/32
Signal/Noise Monitoring - Concept
B. Corcoran et al., “Optical signal processing on a silicon chip at 640Gb/s using slow-light”, Optics Express 18, 7770 (2010)
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.8/32
Bandwidth
640 Gbit/s -> 500fs pulses
B. Corcoran et al., “Optical signal processing on a silicon chip at 640Gb/s using slow-light”, Optics Express 18, 7770 (2010)
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.9/32
2. New colours from cavities
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.10/32
High Q (low loss) comes from lack of radiation within escape cone/ light cone.
High Q cavity
Real space
Fourier space
S. Noda et al., Nature 425, p.944 (2003)
Light cone
Q!45 k
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.11/32
High Q (low loss) comes from lack of radiation within the light cone.
But where does the cavity emission actually go ?
k 0
Farfield
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.12/32
Solution: Secondary grating
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.13/32
Solution: Secondary grating
S. L. Portalupi et al., Optics Express July 2010
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.14/32
!/a!
"
k-!/a!
2!/a!
2!/2a!
a 2a !/a!
Solution: Secondary grating
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.15/32
S. L. Portalupi et al., Optics Express July 2010
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.16/32
M Galli et al. Optics Express, December 2010
Nonlinear effects (here: Second and third harmonic generation) observed due to high intensity buildup and far-field engineering
Harmonic Generation
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.17/32
Ex Nearfield
Model Farfield Experiment Farfield
SHG –surface effect
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.18/32
Ey Nearfield
Model Farfield Experiment Farfield
THG – bulk effect
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.19/32
THG and SHG in Si cavities
M Galli et al. Optics Express, December 2010
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.20/32
Output power
M Galli et al. Optics Express, December 2010
Output power is “absolutely useless for photonics” (Referee NPhot)
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.21/32
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.22/32
! 100 "W
THG emission vs. Nanolaser
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.23/32
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.24/32
3. Silicon (linear) light emission ?
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.25/32
Nature Materials 2005
Bandedge “A-Centre”
“A-type trapping centres….attributed to silicon vacancies” (10K)
“A-Centre”
Defect emission from “A” Centres
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.26/32
“Room-temperature emission at telecom wavelengths from silicon photonic crystal nanocavities” R. Lo Savio et al., accepted for publication in Appl. Phys. Lett.
Defect emission from Hydrogen implants
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.27/32
Nature News & Views, 1997
!
fP =3"3
4# 2QV
!rad =" nonrad
" rad +" nonrad
E. M. Purcell, Phys. Rev. 69, 37 (1946).
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.28/32
!rad =" nonrad
" rad +" nonrad
The Purcell-factor makes defect emission “Room-temperatureable”
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.29/32
Bulk defects (SOITEC process)
Surface defects (Plasma process)
Further improvements ?
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.30/32
!
!
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.31/32
!
1 pW 3000 x SOI
!"µ"Microphotonics S
t. A
ndre
ws
TF Krauss, WavePro No.32/32
Conclusion