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Optical cavity with high quality factor Q. Photonic crystals course final presentation Karin Söderström . Outline. 1) Optical cavities and their use (history) 2) Quality factor Q 3) Lots of cavities 4) Applications of Cavities with PHC Quantum optic
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Optical cavity with high quality factor Q Photonic crystals course final presentation Karin Söderström
Outline 1) Optical cavities and their use (history) 2) Quality factor Q 3) Lots of cavities 4) Applications of Cavities with PHC • Quantum optic • Frequency selective devices Karin Söderström
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 Nature187, 493-494 (1960) Macro-cavity Karin Söderström
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 • Quantum entanglement of radiation and matter is possible P. Michler, A. Kiraz, C. Becher, W. V. Schoenfeld, P. M. Petroff, Lidong Zhang, E. Hu, and A. Imamoglu (2000) Science290 (5500), 2282. Thompson, R. J., Rempe, G. & Kimble, H. J. Phys. Rev. Lett. 68, 1132–1135 (1992). Karin Söderström
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 , Q . The quality of the information . Karin Söderström
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) Karin Söderström
Outline 1) Optical cavities and their use (history) 2) Quality factor Q 3) Lots of cavities 4) Cavities with PHC • Quantum optic • Frequency selective devices Karin Söderström
PHC Cavities Applications • Quantum optics: • Control of the radiative lifetime (Purcell Effect) Fp α Qmode/Vmode Miniature laser, LED, VCSEL, mW threshold Control of the t in a micropillar • Solomon et al,Phys.Rev.lett., 86, 17, 3903, (2001). • Painter,O. et al. Science 284, 1819–1821 (1999). • Applications: • Data transport in optical fiber. • Easy writing and reading of CD, DVD (small spot size) t=1.3ns t=280ps Karin Söderström
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, Nature432, 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) Karin Söderström
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 Karin Söderström
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) Karin Söderström
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) Karin Söderström
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 In this case it is not a bridge: small amount of sample only needed The Caltech Nanofabrication Group Chow et al, Optics letters, 29, 10, 1093, (2004) Karin Söderström
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 Karin Söderström
Thanks for your attention ?Questions? ?Questions? ?Questions? ?Questions? Karin Söderström