Transcript CTI meeting

Optical cavity with high quality
factor Q
Photonic crystals course final
presentation
Karin Söderström
IMT
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
Outline
1) Optical cavities and their use (history)
2) Quality factor Q
3) Lots of cavities
4) Applications of Cavities with PHC
•
•
IMT
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
Quantum optic
Frequency selective devices
Karin Söderström
2
Optical cavities and their use
• The simplest optical cavity: A Fabry-Pérot resonator is
composed of two parallel mirrors
• Associated with an active medium this cavity realized with
one mirror with R<100% leads to one of the greatest
discovery of the century
Laser by Th. Maiman Nature 187, 493-494 (1960)
Macro-cavity
IMT
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
Karin Söderström
3
Optical cavities and their use
• One of the first study on resonator lead to the theoretical
great result:
– By placing a two-level system in a resonator you can modify
(enhance or stop) the spontaneous emission of the two–level
system
E.M.Purcell Phys. Rev. 69 (1946) p. 681
• This information lead to many hope in different field:
– One photon source
P. Michler, A. Kiraz, C. Becher, W. V. Schoenfeld, P. M.
Petroff, Lidong Zhang, E. Hu, and A. Imamoglu (2000)
Science 290 (5500), 2282.
– Quantum entanglement of radiation and matter is possible
Thompson, R. J., Rempe, G. & Kimble, H. J. Phys.
Rev. Lett. 68, 1132–1135 (1992).
IMT
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
Karin Söderström
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Quality factor Q
Definition: Q=Pin the cavity /PLosses α lifetime photon in the cavity t
Q α 1/g where g is the linewidth
If R
IMT
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
Karin Söderström
, Q
. The quality of the information
5
.
Lots of different cavities
Fabry-Pérot cavity made of
two Bragg mirrors
Cavity made by a defect in a photonic
crystal
Kerry J. Vahala, Nature, 424, 6950, 839, (2003)
IMT
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
Karin Söderström
6
Outline
1) Optical cavities and their use (history)
2) Quality factor Q
3) Lots of cavities
4) Cavities with PHC
•
•
IMT
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
Quantum optic
Frequency selective devices
Karin Söderström
7
PHC Cavities Applications
• Quantum optics:
• Control of the radiative lifetime (Purcell Effect)
Miniature laser, LED, VCSEL, mW threshold
Painter,O. et al. Science 284,
1819–1821 (1999).
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
Karin Söderström
Control of the t in a micropillar
Solomon et al,Phys.Rev.lett., 86, 17, 3903, (2001).
Applications:
Data transport in optical fiber.
Easy writing and reading of CD,
DVD (small spot size)
IMT
Fp α Qmode/Vmode
8
t=1.3ns
t=280ps
PHC Cavities Applications
• Quantum optics:
– Strong coupling
(of great interest due to the mode volume)
single-atom cavity quantum electrodynamics in the strong coupling regime
Theoretically proven: Vuckovic et al, Phys. Rev. E, 65, 016608, (2001)
Experimentally shown: Yoshie et al, Nature 432, 200-203 (2004) for a QD
Applications:
Study of center of mass motion: Rempe, Applied physics. B, 60, 233 (1995)
Single photon source: B Deveaud-Pledran, et al - US Patent App. 11/394,518, (2006)
Beauty of physics BEC Theoretical: E Ostrovskaya, Y Kivshar, Optics Exp. vol12, (2004)
IMT
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
Karin Söderström
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PHC Cavities Applications
• Frequency devices (the mode volume is less important)
Akahane et al, Nature, 425, 6961, 944, (2003)
Applications:
Very small spectrometer,
Multiplexer, Demultiplexer, Filters,
Spectroscopy
IMT
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
Karin Söderström
10
PHC Cavities Applications
• Frequency devices (Vmode is less important, here Q=400)
Applications: Very small spectrometer, Multiplexer, Demultiplexer
Noda et al, Nature, 407, 608, (2000)
Shinya et al, Optics Exp,14,
25, 12394, (2006)
IMT
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
Karin Söderström
11
PHC Cavities Applications
• Frequency devices (the mode volume is less important)
Applications: Filters
Qth: 7*10^7
Kuramochi et al, Appl. Phys. Lett., 88,
041112, (2006)
IMT
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
Karin Söderström
12
PHC Cavities Applications
• Frequency devices (the mode volume is less important)
Application: Spectroscopy tool
A photonic crystal sensor with a resolution
of better than Dn =0.002 with a Q factor of 400
The Caltech
Nanofabrication
Group
IMT
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
In this case it is
not a bridge:
small amount of
sample only
needed
Karin Söderström
Chow et al, Optics letters, 29, 10, 1093, (2004)
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Conclusions
• The cavity is the basis to construct devices with photonic
crystals with different functionality modes
– Single photon source needed for quantum computation
• Lots of progresses can be made on Q (from theoretical
studies) but the limits of the fabrication process can be
reached before
• Lots of different applications in many fields
– Laser, spectrometer, multiplexer, filter, spectroscopy
IMT
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
Karin Söderström
14
Thanks for your attention
?Questions?
?Questions?
?Questions?
?Questions?
IMT
INSTITUT DE
MICROTECHNIQUE
NEUCHÂTEL
Karin Söderström
15