Photonic Crystals A New Frontier in Modern Optics

Photonic Crystals: A New Frontier in Modern Optics MARIAN FLORESCU NASA Jet Propulsion Laboratory California Institute of Technology

“ If only were possible to make materials in which electromagnetically waves cannot propagate at certain frequencies, all kinds of almost-magical things would happen” Sir John Maddox, Nature (1990)

Photonic Crystals Photonic crystals: periodic dielectric structures. § interact resonantly with radiation with wavelengths comparable to the periodicity length of the dielectric lattice. § dispersion relation strongly depends on frequency and propagation direction § may present complete band gaps Photonic Band Gap (PBG) materials. Two Fundamental Optical Principles • Localization of Light S. John, Phys. Rev. Lett. 58, 2486 (1987) • Inhibition of Spontaneous Emission E. Yablonovitch, Phys. Rev. Lett. 58 2059 (1987) § Guide and confine light without losses § Novel environment for quantum mechanical light-matter interaction § A rich variety of micro- and nano-photonics devices

Photonic Crystals History 1987: Prediction of photonic crystals S. John, Phys. Rev. Lett. 58, 2486 (1987), “Strong localization of photons in certain dielectric superlattices” E. Yablonovitch, Phys. Rev. Lett. 58 2059 (1987), “Inhibited spontaneous emission in solid state physics and electronics” 1990: Computational demonstration of photonic crystal K. M. Ho, C. T Chan, and C. M. Soukoulis, Phys. Rev. Lett. 65, 3152 (1990) 1991: Experimental demonstration of microwave photonic crystals E. Yablonovitch, T. J. Mitter, K. M. Leung, Phys. Rev. Lett. 67, 2295 (1991) 1995: ”Large” scale 2 D photonic crystals in Visible U. Gruning, V. Lehman, C. M. Englehardt, Appl. Phys. Lett. 66 (1995) 1998: ”Small” scale photonic crystals in near Visible; “Large” scale inverted opals 1999: First photonic crystal based optical devices (lasers, waveguides)

Photonic Crystals- Semiconductors of Light Semiconductors Photonic Crystals Periodic array of atoms Periodic variation of dielectric constant Atomic length scales Length scale ~ Natural structures Artificial structures Control electron flow Control e. m. wave propagation 1950’s electronic revolution New frontier in modern optics

Natural Photonic Crystals: Structural Colours through Photonic Crystals Natural opals Periodic structure striking colour effect even in the absence of pigments

Artificial Photonic Crystals Requirement: overlapping of frequency gaps along different directions § § § High ratio of dielectric indices Same average optical path in different media Dielectric networks should be connected Woodpile structure S. Lin et al. , Nature (1998) Inverted Opals J. Wijnhoven & W. Vos, Science (1998)

Photonic Crystals: Opportunities § Photonic Crystals § complex dielectric environment that controls the flow of radiation § designer vacuum for the emission and absorption of radiation § Passive devices § dielectric mirrors for antennas § micro-resonators and waveguides § Active devices § low-threshold nonlinear devices § microlasers and amplifiers § efficient thermal sources of light § Integrated optics § controlled miniaturisation § pulse sculpturing

Defect-Mode Photonic Crystal Microlaser Photonic Crystal Cavity formed by a point defect O. Painter et. al. , Science (1999)

Photonic Crystals Based Light Bulbs C. Cornelius, J. Dowling, PRA 59, 4736 (1999) “Modification of Planck blackbody radiation by photonic band-gap structures” 3 D Complete Photonic Band Gap Suppress blackbody radiation in the infrared and redirect and enhance thermal energy into visible Solid Tungsten Filament 3 D Tungsten Photonic Crystal Filament S. Y. Lin et al. , Appl. Phys. Lett. (2003) Light bulb efficiency may raise from 5 percent to 60 percent

Solar Cell Applications – Funneling of thermal radiation of larger wavelength (orange area) to thermal radiation of shorter wavelength (grey area). – Spectral and angular control over thermal radiation.

Foundations of Future CI Cavity all-optical transistor Iin Photonic crystal all-optical transistor Iout IH Pump Laser H. M. Gibbs et. al, PRL 36, 1135 (1976) § Fundamental Limitations § switching time • switching intensity = constant § Incoherent character of the switching dissipated power § Operating Parameters § § Holding power: Switching time: Size: 5 m. W 3 µW 1 -0. 5 ns 500 m Probe Laser M. Florescu and S. John, PRA 69, 053810 (2004). § Operating Parameters § Holding power: 10 -100 n. W § Switching power: 50 -500 p. W § Switching time: < 1 ps § Size: 20 m

Single Atom Switching Effect § Photonic Crystals versus Ordinary Vacuum § § Positive population inversion Switching behaviour of the atomic inversion M. Florescu and S. John, PRA 64, 033801 (2001)

Quantum Optics in Photonic Crystals § Long temporal separation between incident laser photons § Fast frequency variations of the photonic DOS § § Band-edge enhancement of the Lamb shift Vacuum Rabi splitting T. Yoshie et al. , Nature, 2004.

Foundations for Future CI: Single Photon Sources § Enabling Linear Optical Quantum Computing and Quantum Cryptography § § fully deterministic pumping mechanism very fast triggering mechanism accelerated spontaneous emission PBG architecture design to achieve prescribed DOS at the ion position M. Florescu et al. , EPL 69, 945 (2005)

CI Enabled Photonic Crystal Design (I) Photo-resist layer exposed to multiple laser beam interference that produce a periodic intensity pattern 10 m Four laser beams interfere to form a 3 D periodic intensity pattern O. Toader, et al. , PRL 92, 043905 (2004) 3 D photonic crystals fabricated using holographic lithography M. Campell et al. Nature, 404, 53 (2000)

CI Enabled Photonic Crystal Design (II) O. Toader & S. John, Science (2001)

CI Enabled Photonic Crystal Design (III) S. Kennedy et al. , Nano Letters (2002)

Multi-Physics Problem: Photonic Crystal Radiant Energy Transfer Photonic Crystals Optical Properties Rethermalization Processes: Transport Properties: Photons Electrons Phonons Metallic (Dielectric) Backbone Electronic Characterization Photons Electrons Phonons

Summary Photonic Crystals: Photonic analogues of semiconductors that control the flow of light PBG materials: Integrated optical micro-circuits with complete light localization Designer Vacuum: Frequency selective control of spontaneous and thermal emission enables novel active devices Potential to Enable Future CI: Single photon source for LOQC All-optical micro-transistors CI Enabled Photonic Crystal Research and Technology: Photonic “materials by design” Multiphysics and multiscale analysis