Transcript Polariton Physics and Devices Pavlos G. Savvidis Microelectronics Group

Polariton Physics and Devices
Pavlos G. Savvidis
Dept of Materials Sci. & Tech
Microelectronics Group
University of Crete / IESL
Engineering Light Matter Interactions
• modify photonic and electronic wavefunctions
in semiconductor heterostructures
d~l
AlAs
AlAs
T
QD
eδ
high finesse
cavity
l
GaAs
Confined electronic states:
band gap energy modulation
photons: refractive index modulation
• enhance, inhibit spontaneous radiation
• new properties, novel interactions, novel emitters
FORTH
Microelectronics Research Group
Univ. of Crete
Weak Coupling Regime
γ: loss channel (e.g. imperfect
Ω
γ
Weak Coupling Regime (γ>>Ω) :
mirror)
Ω coupling strength between
optical transition of the material and
the resonance photon mode
emitted photon leaves the resonator
(after some reflections) no
reabsorption
 Spontaneous Emission is
irreversible
FORTH
Microelectronics Research Group
Univ. of Crete
Strong Coupling Regime
γ: loss channel
γ
Ω
Strong Coupling Regime (Ω>>γ) :
Ω coupling strength between
optical transition of the material and
the resonance photon mode
emitted photon will be reabsorbed
before it leaves the cavity
 Spontaneous Emission is a
reversible process
Polaritons
FORTH
Microelectronics Research Group
Univ. of Crete
Research Activities
GaAs Polariton LEDs & Lasers
• Ultralow threshold lasers
Bragg Polaritons
Strong Coupling in GaN Microcavties
• Robust polariton devices at RT
Hybrid Organic-Inorganic LEDs
• Very strong nonlinearities
- common idea of engineering light matter interactions at nanoscale
Polariton Light Emitting Diode (LED)
Polariton electroluminescence up to room temperature
EL intensity
Temperature (K)
C
X
190
190
200
200
210
210
220
220
230
230
240
240
250
250
260
260
C
X
1.330
1.330
1.335
1.335
1.340
1.340
1.345
1.345
Energy (eV)
1.350
1.350
1.355
1.355
1.360
1.360
S.I. Tsintzos, N.T. Pelekanos, G. Konstantinidis, Z. Hatzopoulos, P. G. Savvidis, Nature 453, 372 (2008)
Strong exciton-Bragg mode coupling regime
Bragg polaritons
30K
A. Askitopoulos et al., Phys. Rev. Lett. 106, 076401 (2011)
People
Group
Prof. PG Savvidis
Dr. Peter Eldridge
Dr. Simos Tsintzos
Dr. Manolis Trichas
PhD Niccolo Somaschi
PhD Panos Tsotsis
PhD Tingge Gao
PhD Kostas Daskalakis
Collaborators
Alumni
MS A. Askitopoulos
MS C. Xenogianni
MS N. Xatzidimitriou
MS P. Tsotsis
Prof. Pelekanos
Materials
Prof. Z. Hatzopoulos Physics
Prof. Iliopoulos
Physics
Prof. I Perakis
Physics
University of Cambridge
University of Sheffield
Prof. J. J. Baumberg
Dr. G. Christmann
Prof D. Lidzey
University of Southampton
Prof P. Lagoudakis
Dr. G. Kostantinidis IESL
Dr. G. Deligeorgis
IESL
University of Durham
Prof. M. Kaliteevski
SelectedFunding
Publications
Principle Investigator in:
EU FP7 : ITN grants
A. Askitopoulos,
Rev. Lett. 106,Polariton
076401 (2011)
2009-2013 Phys.
“CLERMONT4”
Lasers
G. Christmann,
Appl.
Phys. Lett. 98, 081111
2009-2013
“ICARUS”
Hybrid(2011)
Materials
G Dialynas, J. Appl. Phys. 108, 103525 (2010)
G. Christmann,
National:Phys. Rev. B 82, 113308 (2010)
E. Trichas, Appl. Phys. Lett. 94, 173505 (2009)
2005-2010 PENED’03
GaN Microcavities
S. I. Tsintzos, Appl. Phys. Lett. 94, 071109 (2009)
2006-2010 Pythagoras II Organic Microcavities
G. E. Dialynas, Int. Jour.l of Nanotechnology 6, 124 (2009)
2010-2013
Herakleitos
Polariton Devices
S. I. Tsintzos,
Nature
453, 372II(2008)
Industrial
Mesophotonics Ltd. (PENED’03)
Total Funding 2005-2010 : ~ 1M Euro
Ultrafast Lab
New Physics & Applications
• Strong-coupling provides a new insight into a number of very
interesting fundamental physical processes
Polaritons are Bosons
- Bose condensation
- stimulated scattering
Polariton vs Photon
Laser
Deng, et al. Natl. Acad.
Sci. 15318 (2003)
- ultralow threshold polariton lasers
- all optical switches and amplifiers
FORTH
Microelectronics Research Group
Univ. of Crete