polariton physics and devices pavlos g. savvidis dept of materials sci. & tech microelectronics...
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Polariton Physics and Devices
Pavlos G. Savvidis
Dept of Materials Sci. & TechMicroelectronics GroupUniversity of Crete / IESL
d
Engineering Light Matter Interactions
• modify photonic and electronic wavefunctionsin semiconductor heterostructures
Confined electronic states: band gap energy modulation
photons: refractive index modulation
• enhance, inhibit spontaneous radiation• new properties, novel interactions, novel emitters
AlAs
GaAs
AlAs
e-
high finessecavity
FORTH Microelectronics Research Group Univ. of Crete
T
δ
QD
Weak Coupling Regime
γ: loss channel (e.g. imperfectmirror)
Ω coupling strength betweenoptical transition of the material andthe resonance photon mode
Weak Coupling Regime (γ>>Ω) :
emitted photon leaves the resonator(after some reflections) no reabsorption
Spontaneous Emission is irreversible
FORTH Microelectronics Research Group Univ. of Crete
γΩ
Strong Coupling Regime
γ: loss channel
Ω coupling strength betweenoptical transition of the material andthe resonance photon mode
Strong Coupling Regime (Ω>>γ) :
emitted photon will be reabsorbed before it leaves the cavity
Spontaneous Emission is a reversible process
Polaritons
FORTH Microelectronics Research Group Univ. of Crete
γΩ
Research Activities
GaAs Polariton LEDs & Lasers Strong Coupling in GaN Microcavties
- common idea of engineering light matter interactions at nanoscale
Bragg Polaritons
• Ultralow threshold lasers • Robust polariton devices at RT
• Very strong nonlinearities
Hybrid Organic-Inorganic LEDs
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EL intensity
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Energy (eV)
Polariton Light Emitting Diode (LED)
S.I. Tsintzos, N.T. Pelekanos, G. Konstantinidis, Z. Hatzopoulos, P. G. Savvidis, Nature 453, 372 (2008)
Polariton electroluminescence up to room temperature
Strong exciton-Bragg mode coupling regime
Bragg polaritons
A. Askitopoulos et al., Phys. Rev. Lett. 106, 076401 (2011)
30K
People
Prof. PG SavvidisDr. Peter Eldridge
Dr. Simos Tsintzos
Dr. Manolis Trichas
PhD Niccolo Somaschi
PhD Panos Tsotsis
PhD Tingge Gao
PhD Kostas Daskalakis
Alumni
MS A. Askitopoulos
MS C. Xenogianni
MS N. Xatzidimitriou
MS P. Tsotsis
Collaborators
Prof. Pelekanos Materials
Prof. Z. Hatzopoulos Physics
Prof. Iliopoulos Physics
Prof. I Perakis Physics
University of Durham
Prof. M. Kaliteevski
University of SheffieldProf D. Lidzey Prof. J. J. Baumberg
Dr. G. Christmann
University of Cambridge
University of SouthamptonProf P. Lagoudakis
Dr. G. Kostantinidis IESLDr. G. Deligeorgis IESL
Group
Funding
EU FP7 : ITN grants
2009-2013 “CLERMONT4” Polariton Lasers2009-2013 “ICARUS” Hybrid Materials
National: 2005-2010 PENED’03 GaN Microcavities2006-2010 Pythagoras II Organic Microcavities2010-2013 Herakleitos II Polariton Devices
Industrial Mesophotonics Ltd. (PENED’03)
Total Funding 2005-2010 : ~ 1M Euro
Principle Investigator in:
A. Askitopoulos, Phys. Rev. Lett. 106, 076401 (2011)G. Christmann, Appl. Phys. Lett. 98, 081111 (2011)G Dialynas, J. Appl. Phys. 108, 103525 (2010)G. Christmann, Phys. Rev. B 82, 113308 (2010)E. Trichas, Appl. Phys. Lett. 94, 173505 (2009)S. I. Tsintzos, Appl. Phys. Lett. 94, 071109 (2009)G. E. Dialynas, Int. Jour.l of Nanotechnology 6, 124 (2009)S. I. Tsintzos, Nature 453, 372 (2008)
Selected Publications
Ultrafast Lab
Polaritons are Bosons
- Bose condensation - stimulated scattering
• Strong-coupling provides a new insight into a number of very interesting fundamental physical processes
New Physics & Applications
FORTH Microelectronics Research Group Univ. of Crete
- ultralow threshold polariton lasers - all optical switches and amplifiers
Polariton vs Photon LaserDeng, et al. Natl. Acad. Sci. 15318 (2003)