Abstract : We demonstrate in the near infrared the coupled-resonator
optical waveguide (CROW), concept recently
proposed by Yariv et al. [Optics Letters 24, 711 (1999)]. 2D photonic
crystals have been used to define, in a GaAs-based
waveguiding heterostructure, an array of micron-sized hexagonal cavities
coupled through thin walls. Using the
photoexcitation of InAs quantum dots as an internal source, the transmission
spectra of the coupled resonators show
marked minibands and minigaps, in agreement with theoretical predictions.
Optics Letters, vol.26, pp.1019-1021, 2001
Laboratoire de Physique de la Matière Condensée, Ecole Polytechnique, UMR 7643 CNRS, 91128 Palaiseau Cedex - France
*Optoelectronics Research Group, University of Glasgow, Glasgow G12 8LT, Scotland
**School of Physics and Astronomy, University of St Andrews, St Andrews,
Fife, KY16 9SS, Scotland
? Institut de Micro et Opto-électronique, Ecole Polytechnique
Fédérale de Lausanne, CH-1015 Lausanne - Switzerland
* Now at Intense Photonics Ltd., 1 Kelvin Campus, West of Scotland Science Park, Glasgow G20 0SP, Scotland.
Abstract: We report on the investigation of cavities coupled to channel waveguides defined in a triangular-lattice photonic crystal etched into a GaAs/AlGaAs heterostructure waveguide. We make use of the internal probe technique by selectively exciting the photoluminescence of InAs dots embedded in the planar waveguide. We collect at the nearby cleaved edge the fundamental mode transmitted through the channel waveguides. From the study of a number of basic cases, we exemplify how one may deduce the main guideline design rules for given cavity-guide interaction mechanisms and then for the implementations of functions such as bending and filtering. In particular, the role of the so-called mini-stopband feature of the waveguide and the role of the cavity mode degeneracy are outlined.
Journal of Quantum Electronics, to be published, 2002
S. Olivier, H. Benisty, C. Weisbuch , C.J.M. Smith*, T.F. Krauss**,
R. Houdré?, U. Oesterle?.
Laboratoire de Physique de la Matière Condensée, Ecole Polytechnique, 91128 Palaiseau, France
*Optoelectronics Research Group, University of Glasgow, Glasgow G12
8LT, Scotland
**School of Physics and Astronomy, Universityof St Andrews, St Andrews,
Fife, KY16 9SS, Scotland
? Institut de Micro et Opto-électronique, Ecole Polytechnique
Fédérale de Lausanne, CH-1015 Lausanne - Switzerland
* Now at Intense Photonics, 4 Stanley Boulevard, High Blantyre, G72 0UX, Scotland.
Abstract :
We compare quantitatively the transmission properties of various 60°
bends carved into a photonic crystal based on a two-dimensional triangular
lattice of holes perforating a GaAs-based heterostructure. The bends are
inserted into channel waveguides defined by three missing rows in the photonic
crystal. Their design is inspired by some ideas from classical integrated
optics. We show experimentally that in some cases the transmission of the
bent waveguide is fairly high, up to 70%, within a bandwidth of 3%, e.g.
30 nm at 1µm, sufficient to contemplate WDM applications. The observed
performance opens the opportunity to implement a variety of optical functions
in view of future photonic crystal integrated circuits for which low-loss
bends constitute an essential building-block.
Journal of Lightwave Technology, to be published, 2002
H. Benisty, S. Olivier, C. Weisbuch , M. Agio(*,ii), M. Kafesaki(i),
C.M. Soukoulis(i,ii) Min Qiu**, M. Swillo**, A. Karlsson**, B. Jaskorzynska,**
A. Talneau***, J. Moosburger?, M. Kamp? A. Forchel?, R. Ferrini??, R. Houdré??,
U. Oesterle??.
Laboratoire de Physique de la Matière Condensée, Ecole Polytechnique, UMR 7643 CNRS, 91128 Palaiseau Cedex - France
*INFM - Dipartimento di Fisica "A. Volta", Università di Pavia,
via Bassi 6, I-27100 Pavia, Italy
(i)Research Center of Crete, P.O. Box 1527, 71110 Heraklion,
Crete, Greece
(ii)Ames Laboratory and Department of Physics and Astronomy
Iowa State University, Ames, IA 50011
** Department of Microelectronics and Information Technology, Royal
Institute of Technology,
164 40 Kista, Sweden
***Laboratoire de Physique et Nanostructures, CNRS, 192 Ave H. Ravéra, 92225 Bagneux cedex,France
? Technische Physik, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
? ? Institut de Micro et Opto-électronique, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne - Switzerland
Abstract :
One of the essential building-blocks towards miniature photonic-crystal
based photonic integrated circuits is a sharp bend. Our group has focussed
on two-dimensional photonic crystal based on a triangular lattice of holes
perforating a standard heterostructure. This latter, GaAlAs-based or InP-based
is vertically a monomode waveguide. We consider essentially one or two
60° bends defined by one to five missing-rows, spanning both cases
of monomode and multi-mode channel waveguides. From intensive modeling
and various experimental measurements (both on GaAs and InP), we point
out the origin of the present level of bend insertion losses and discuss
the merits of the many roads open for improved design.
Journal of Quantum Electronics, to be published, 2002
M. Qiu
Laboratory of Photonics and Microwave Engineering), Royal Institute
of Technology),
164 40 Kista, Sweden
C. J. M. Smith
Intense Photonics, 1 Kelvin Campus, West of Scotland Science Park,
Glasgow G20 0SP, Scotland.
R. Houdré, U. Oesterle
Institut de Micro- et Opto-electronique, Ecole Polytechnique Fédérale
de Lausanne,
Lausanne CH-1015, Switzerland.
Abstract: We have measured the near-infrared transmission spectra of
60° bends defined in two-dimensional photonic crystal waveguides consisting
of three missing rows. Two limit cases are studied: a basic non-resonant
bend and a bend built around a resonant lozenge cavity, which is found
to exhibit peaked transmission. Finite-difference-time-domain (FDTD) simulations
show very good agreement with the data allowing general design issues for
efficient bends to be discussed.
Applied Physics Letters, vol.79, pp.2514-2516, 2001
Appl. Phys. Lett., vol. 79, pp. 3579-3581, 2001
Abstract : We study the transmission properties of straight channel
waveguides designed in a two-dimensional photonic
crystal patterned into an AlGaAs heterostructure. 2D dispersion calculations
show the existence of small gaps occuring
along the dispersion branch of the fundamental mode. We show that their
location agree very well with mini-stop bands
observed on the transmission spectra.
Optical and Quantum Electronics, special issue on photonic crystals 2002, vol.34, pp.171-181, 2002
S. Olivier, M. Rattier, H. Benisty, C. Weisbuch
Laboratoire Physique de Matière Condensée, Ecole Polytechnique,
91128 Palaiseau Cedex, France
C. J. M. Smith, R. M. De La Rue
Optoelectronics Research Group, University of Glasgow, Glasgow G12
8LT, Scotland
T. F. Krauss
School of Physics and Astronomy, University of St. Andrews, St. Andrews,
KY16 9SS, Scotland
U. Oesterle, R. Houdré
Institut de Micro- et Opto-é lectronique, Ecole Fédérale
de Lausanne, CH-1025 Lausanne, Switzerland
We show that a channel waveguide in a two-dimensional photonic crystal
channel can be considered as a periodic
one-dimensional system. Waveguides were fabricated into a GaAs/AlGaAs
waveguide heterostructure and the waveguide
transmission was measured by detecting the guided photoluminescence
of embedded InAs quantum dots excited near the
guide entrance. Mini stopbands related to anticrossings in the dispersion
were observed and the spectral location and
width of these transmissions stopbands is found to agree well with
calculated values.
Physical Review B, vol. 63, pp. 113311, 2001
We demonstrate, in a planar two dimensional (2D) configuration, in the
optical regime a clear association of two photonic
crystal elements and the ability to produce a low-loss coupled system.
A channel waveguide is brought to between 2 and 5
crystal rows (450 to 1126 nm) from a 2D microcavity fabricated in a
GaAs/AlGaAs waveguide. We probe these two
elements individually and explore their interaction.
Applied Physics Letters, Vol. 78, No. 11, pp. 1487-1489, 12 March 2001
C. J. M. Smith
Optoelectronics Research Group, Glasgow University, Glasgow G12 8LT,
Scotland
H. Benisty, S. Olivier, M. Rattier, and C. Weisbuch
Laboratoire Physique de la Matière Condensée, Ecole Polytechnique,
91128 Palaiseau Cedex, France
T. F. Krauss
School of Physics and Astronomy, St. Andrews University, St. Andrews
KY16 9SS, Scotland
R. M. De La Rue
Optoelectronics Research Group, Glasgow University, Glasgow G12 8LT,
Scotland
R. Houdré and U. Oesterle
IMO, Ecole Polytechnique Fédérale de Lausanne, CH-1025
Lausanne, Switzerland
(Received 11 July 2000; accepted 6 September 2000)
We have used transmission measurements to estimate the propagation loss
of submicron channels defined in
two-dimensional photonic crystals patterned into a Ga(Al)As waveguide.
The measured propagation loss of the
fundamental mode is indistinguishable from the material absorption,
setting an upper limit of 50 cm?1 (2 dB per 100 µm).
We also find that, provided the etching is deep enough, propagation
losses of these photonic crystal waveguides are lower
than those of ridge waveguides etched in the same run. ©2000 American
Institute of Physics.
Applied Physics Letters -- October 30, 2000 -- Volume 77, Issue 18, pp. 2813-2815
H. Benisty
Laboratoire de Physique de la Matière Condensée, URA
124 du CNRS, Ecole Polytechnique, F-91128 Palaiseau cedex,France
(Received 18 September 1995; accepted 1 February 1996)
Guided modes propagating in dielectric material surrounded by periodic
two-dimensional photonic band-gap material are
theoretically studied using the plane-wave expansion and a supercell.
Two opposite boundary designs heavily affecting
optical feedback at zone edge (Bragg reflection) are investigated.
Limits to the validity range of simple bi-mode coupling
schemes in these periodic guides are emphasized and coupling coefficients
presented in adequate cases. Mode symmetries
are studied and related to dispersion and frequency-width relationship.
Finally, the smallest guide thickness allowing for a
midgap mode is found to be much smaller than the analogous one-dimensional
case, raising prospects for enhanced
light-matter interaction. ©1996 American Institute of Physics.
Journal of Applied Physics -- May 15, 1996 -- Volume 79, Issue 10, pp. 7483-7492
Maxime Rattier, Henri Benisty, Christopher J.M. Smith, Alexandre
Béraud, David Cassagne, Christian Jouanin,
Thomas F. Krauss and Claude Weisbuch
Abstract--As a step towards the use of photonic crystals in optoelectronic
devices, we present a thorough study of
two-dimensional photonic-crystal mirrors etched into a GaAs/AlGaAs
planar waveguide. Fabry-Pérot resonators are
fabricated to deduce the reflectivity, transmission, losses, as well
as penetration lengths of these mirrors. The guided
photoluminescence of InAs quantum dots embedded in GaAs is used to
obtain the transmission spectra of these cavities.
The varying thickness between the mirrors allows a scan across the
whole bandgap spectral range. Quality factors (up to
200) and peak transmissions (up to 0.3) are measured showing that mirrors
of four rows of holes have 88 % reflectivity, 6
% transmission and 6 % losses. Losses are also related to a two-dimensional
transfer matrix method calculation including
a recently introduced scheme to account for losses.
IEEE Journal of Quantum Electronics, Volume 37, Issue 2, February 2001, pages 237 - 243
C. J. M. Smith,* H. Benisty, M. Rattier, T. F. Krauss,* U.Oesterle,à
R. Houdréà & C. Weisbuch
Journal of the Optical Society of America B, to be published in the
December 2000 issue
* Optoelectronics Research Group, University of Glasgow, Glasgow G12
8LT, Scotland.
Laboratoire Physique de la Matière Condensée, Ecole
Polytechnique, Palaiseau 91128, France.
à Institut de Micro- et Opto-électronique, Ecole Polytechnique
Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
ABSTRACT: We report on sixfold symmetric cavities bounded by a two-dimensional
triangular photonic-crystal lattice
etched into a GaAs/AlGaAs laserlike heterostructure. InAs quantum dots
embedded in the GaAs waveguide core are
excited inside the cavities and provide an effective probe of the cavity
resonances. Varying degrees of confinement are
observed, depending on the overlap of the emission of the probe beam
and the spectral position of the in-plane stop
bands. The directional characteristics of these cavities are examined
also by the introduction of perturbations to the
confining crystal. Simulations provide a useful insight into the measured
results and highlight the route for integration of
these cavities with photonic-crystal waveguides. 2000 Optical Society
of America
JOSA B, Volume 17, Issue 12, 2043-2051 December 2000
Abstract : We address the issue of out-of-plane losses in two-dimensional
photonic crystals (PC) etched through a GaAs
monomode waveguide cladded with standard GaAlAs alloys. We correlate
experimental transmission of PCs with two kinds
of loss simulation results. The first kind is 2D and introduces an
ad hoc imaginary index in the air holes to account for the
losses [H. Benisty et al., Appl. Phys. Lett., 76, 532 (2000)]. The
second kind is a novel exact three-dimensional calculation
inspired by grating-Fourier analysis that provides quantitatively unprecedented
agreement with experimental
measurements taking into account hole depth as a limiting parameter.
We conclude that, in revision to the conclusions of
the above reference, the experimental losses are not the intrinsic
ones, being larger by a factor of 5 to 10 due to
insufficient hole depth. The transition occurs at a critical etch depth
shown to be here around 700 nm. We thus predict, for
holes deeper than 700 nm, much improved crystals with very low transmission
losses and microresonators with ultra-high
quality factors.
Optical and Quantum Electronics, special issue on photonic crystals 2002, vol.34, pp.205-215, 2002
Laboratoire de Physique de la Matière Condensée, Ecole Polytechnique, 91128 Palaiseau Cedex, France
Christopher J.M. Smith*
Optoelectronics Research Group, University of Glasgow, Glasgow G12 8LT, Scotland
*Now at Intense Photonics, 4 Stanley Boulevard, High Blantyre, G72 0UX, Scotland.
Thomas F. Krauss
School of Physics and Astronomy, University of St Andrews, St Andrews, Fife, KY16 9SS, Scotland
Romuald Houdré and Ursula Oesterle
Institut de Micro et Opto-électronique, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne - Switzerland
Abstract: We analyse the transmission of planar photonic crystal channel waveguides consisting of three missing rows in a triangular lattice of air holes, and modified at both ends by constrictions. The structures are fabricated into a GaAs/AlGaAs heterostructure, in which an internal source consisting of three layers of quantum dots is embedded. The constrictions induce peculiar spectral features that are used to improve the sensitivity of transmission measurements to propagation losses. Two effects are evidenced: (i) the constrictions act as mirrors, inducing Fabry-Pérot fringes on the transmitted spectra; (ii) they also induce a mode-mixing process, mostly between the fundamental and the third transverse modes of the waveguides. Using the visibility of the resulting two-mode fringes, observed on the transmitted spectra, we extract a quantitative value for propagation losses at : a1 = 25cm-1(1dB per )for the fundamental mode.
Journal of the Optical Society of America B, submitted, 2002
Journal of the Optical Society of America, to be submitted, 2002
A method for the electromagnetic analysis of photonic crystal waveguides
is described. It is tested against experimental
transmission data obtained for AlGaAs slab-waveguide structures perforated
by a two-dimensional hexagonal lattice. A
good quantitative agreement is obtained for the band edge locations,
for the ripples in the transmission windows, and
more importantly, for the out-of-plane losses induced by the finite
hole depth. The ultimate performance of the structure
for deep etched holes is predicted. ©2001 American Institute of
Physics.
(Received 17 July 2000; accepted 16 October 2000)
Journal of Applied Physics -- January 15, 2001 -- Volume 89, Issue 2, pp. 1512-1514
M. Qiu, B. Jaskorzynska, M. Swillo
Laboratory of Photonics and Microwave Engineering, Department of Microelectronics
and Information Technology, Royal Institute of Technology (KTH), Electrum
229, 164 40 Kista, Sweden
Henri Benisty
Laboratoire de Physique de la Matière Condensée, Ecole
Polytechnique,
91 128 Palaiseau, France
Abstract
Devices based on two-dimensional (2D) photonic crystals (PCs) are typically
realized as 3D structures consisting of an array of holes (or rods) vertically
etched through a slab waveguide. The existence of holes in a slab waveguide
may induce strong radiation losses to the slab claddings. Exact modelling
of devices affected by such out-of-plane losses requires 3D calculations.
A more efficient, approximate method previously introduced in the frequency-domain
consists in including an effective loss into 2D models through a dissipation
mechanism (an imaginary part of the dielectric constant) in the air holes.
In the present work, we extend the method to the time-domain by assuming
that the air holes exhibit a nonvanishing conductivity. Employing the 2D
finite-difference time-domain method, and the effective-index method to
account for the vertical confinement, we simulated a number of experimentally
studied PC structures (cavities, waveguides and bends). We show that a
remarkably good agreement with all experiments can be obtained using the
effective loss approach.
Journal of Lightwave Technology, to be published, 2002
D. Cassagne, and C. Jouanin
Groupe d'Etude des Semiconducteurs, Université Montpellier II CC074, 34095 Montpellier Cedex 05, France
R. Houdré , U. Oesterle and V. Bardinal*
Institut de Micro et Opto-électronique, Ecole Polytechnique Fédérale de Lausanne, CH-1015 LAUSANNE - SWITZERLAND (*) On leave fromm LAAS, CNRS, Toulouse, France
Received: 29 October 1998; revised :6 April 1999;
Abstract :We report on the measurement of the diffraction efficiency of two-dimensional photonic-bandgap lattices consisting of a triangular array of circular air holes etched in a semiconductor waveguide. We use the spontaneous emission of the material as an internal point source. Combined to previous reflectivity and transmission measurements, [Phys. Rev. Lett., vol. 79, pp.4147-4150, 1997], the diffraction data allow us to assess the total amount of out-of-plane losses experienced by a guided wave traversing the dielectric lattice, as a function of the lattice pitch. We found that these losses are particularly weak for some range of parameters, especially in the photonic bandgap of interest. We discuss the reasons why they can be substantial with other parameters.© 1999 IEEE. [S0018-9197(99)05255-0]
IEEE Journal of Quantum Electronics, Vol. 35, No. 7, pp. 1045-1052, 7 July 1999
Received: 22 June 1999; accepted: 4 December 1999
Radiation losses occurring in photonic crystals etched into planar waveguides are analyzed using a first-order perturbation approximation. Assuming the incoherent scattering limit, the model indicates that losses diminish as the cladding index approaches the core index. A simple scheme is devised to include these losses into purely two-dimensional calculations by using an imaginary index. Such calculations are shown to agree with corresponding experimental transmission through near-infrared photonic crystals, reproducing the contrasting behavior of the "dielectric" and "air" band edges. © 2000 American Institute of Physics. [S0003-6951(00)03205-8]
Applied Physics Letters, Vol. 76, No. 5, pp. 532-534, 31 January 2000
Received: 12 August 1999;
Abstract : We describe experiments on a quasi two-dimensional optical system consisting of a triangular array of air cylinders etched through a laser-like Ga(Al)As waveguiding heterostructure. Such a configuration is shown to yield results very well approximated by the infinite 2D photonic crystal. We first present a set of measurements of the optical properties (transmission, reflection and diffraction) of slabs of these photonic crystals, including the case of in-plane Fabry-Perot cavities formed between two such crystals. The measurement method makes use of the guided photoluminescence of embedded quantum wells or InAs quantum dots to generate an internal probe beam. Out-of-plane scattering losses are evaluated by various means. In a second part, in-plane micron-sized photonic boxes bounded by circular trenches or by two-dimensional photonic crystal are probed by exciting spontaneous emission inside them. The high quality factors observed in such photon boxes demonstrate the excellent photon confinement attainable in these systems and allow to access the detail of the modal structure. Some perspectives for applications are finally offered. ©1999 IEEE.
IEEE Journal of Lightwave Technology, Vol. 17, No. 11, pp. 2063-2077, 11 November 1999
Abstract: Photonic crystals have seen major advances in the past few
years in the optical range. Three-dimensional (3D)
structures are now made by several self-organized growth methods. While
full 3D photonic bandgaps are clearly observed,
physical effects such as spontaneous emission control or lifetime changes
are weak, due to the regular nature of
self-organized structures. On the other hand, the association of in-plane
waveguiding and two-dimensional photonic
crystals (PCs) in thin-slab or waveguide structures leads to good 3D
confinement with easy fabrication. They open many
exciting opportunities in optoelectronic devices and integrated optics.
We present experiments on a variety of structures
and devices, as well as modelling tools, which show that 2D PCs etched
through waveguides supported by substrates are
a viable route to high-performance PC-based photonic integrated circuits
(PICs).
Physica Status Solidi B-Basic Research 221: (1) 93-99 SEP 2000
Proceedings of the SPIE, 2001
Proceedings of the IEICE, vol.E84-C, pp.660-668, 2001
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H. Benisty, C. Weisbuch, D. Labilloy, M. Rattier
Abstract: Wavelength-scale periodically structured dielectrics in two
or three dimensions, the so-called photonic crystals
(PCs), may acquire outstanding electromagnetic properties, due to the
appearance of a photonic gap and of the peculiar
photon dispersion relations around such gaps. One may take advantage
of these properties to elaborate novel devices
based on microresonators, integrated mirrors, etc. In this paper, we
start with a brief introduction to two-dimensional
(2D) crystals and to defects in these crystals. We next discuss the
physical and technological issues raised by some recent
realisations. The incorporation of PCs into various devices is then
examined, restricting ourselves to applications to
light-emitters and integrated optics, a case for which radiation losses
of PCs, are discussed. (C) 2000 Published by Elsevier
Science B.V.
Applied Surface Science 164: 205-218 SEP 1 2000
We present continuous near-infared transmission measurements of two-dimensional photonic crystals etched through a (Ga,Al)As waveguide. We use photoluminescence of InAs self-organized quantum dots as an internal source with a broad guided spectrum. Transmission spectra exhibit both a marked gap for the TE polarization and a fine structure consisting of transmission oscillations around it. This fine structure is exploited to assess the fabrication parameters and to determine the band structure of the photonic crystal. ©1999 The American Physical Society
We present quantitative measurements of the interaction between a guided optical wave and a two-dimensional photonic crystal using spontaneous emission of the material as an internal point source. This is the first analysis at near-infrared wavelengths where transmission, reflection, and in-plane diffraction are quantified at the same time. Low transmission coincides with high reflection or in-plane diffraction, indicating that the light remains guided upon interaction. Also, good qualitative agreement is found with a two-dimensional simulation based on the transfer matrix method. ©1997 The American Physical Society
Physical Review Letters -- November 24, 1997 -- Volume 79, Issue 21, pp. 4147-4150
We describe an experimental setup, which allows assessing the optical properties of two-dimensional photonic crystals combined with a waveguide geometry, and etched into a light-emitting (GaAs/InGaAs) semiconductor. By means of a guiding layer, the spontaneous emission of the material is used as a built-in source to probe the properties of the etched microstructure, conveniently compared to the usual measurement schemes. We show polarized transmission and coefficients largely depending on the photonic crystal orientation. ©1997 American Institute of Physics.
Applied Physics Letters -- August 11, 1997 -- Volume 71, Issue 6, pp. 738-740
Guided modes propagating in dielectric material surrounded by periodic two-dimensional photonic band-gap material are theoretically studied using the plane-wave expansion and a supercell. Two opposite boundary designs heavily affecting optical feedback at zone edge (Bragg reflection) are investigated. Limits to the validity range of simple bi-mode coupling schemes in these periodic guides are emphasized and coupling coefficients presented in adequate cases. Mode symmetries are studied and related to dispersion and frequency-width relationship. Finally, the smallest guide thickness allowing for a midgap mode is found to be much smaller than the analogous one-dimensional case, raising prospects for enhanced light-matter interaction. ©1996 American Institute of Physics.
Journal of Applied Physics -- May 15, 1996 -- Volume 79, Issue 10, pp. 7483-7492
We made disk-shaped microcavities of approximately 10 µm2 in area in a GaAs/AlGaAs waveguide structure by etching deep vertical concentric trenches. The trenches form a circular Bragg-like reflector that confines light in the remaining two lateral dimensions. We demonstrate from photoluminescence excited in the waveguide the confinement of discrete disk modes whose wave vector is mainly radial, in contrast with whispering gallery modes. Their quality factors up to Q = 650 indicate in-plane reflectivities approaching 90%. In the near infrared, this represents a demonstration of wavelength-scale light confinement based on photonic crystal effects in two dimensions. ©1998 American Institute of Physics.
Applied Physics Letters -- September 7, 1998 -- Volume 73, Issue 10, pp. 1314-1316
The lasing properties of quantum well structures, where the cavity is defined in the plane of the wells by circular Bragg reflectors are investigated. Diffraction of the in-plane lasing modes into the vertical direction by the circular distributed Bragg reflector (DBR) allows the simultaneous measurement of near-field emission patterns and emission spectra, allowing unambiguous assignment of azimuthal quantum numbers to the lasing modes. The radial quantum number is determined by fitting the lasing spectrum to theory. Lasing is shown to occur in modes whose wave vector is mainly radial, confined by the circular DBR structure, rather than in whispering gallery type modes which are mainly azimuthal. ©1999 American Institute of Physics.
Applied Physics Letters -- November 15, 1999 -- Volume 75, Issue 20, pp. 3051-3053
In-plane microresonators consisting of an AlxGa1-xAs heterostructure waveguide and deep etched cylindrical trenches give both out-of-plane and lateral-light confinement. The air trenches, acting as a Bragg reflector also allow diffraction into air, so that the far-field pattern reveals interesting information on the resonant cavity modes. By the use of a two-dimensional cylindrical model and a transfer-matrix method based on Hankel functions, the energy and angular dependences of the diffracted field are calculated and successfully compared to measurements. ©2000 The American Physical Society
MAXIME RATTIER1, THOMAS F. KRAUSS2, JEAN-FRANÇOIS
CARLIN3, ROSS STANLEY3, URSULA OESTERLE3, ROMUALD HOUDRÉ3, CHRISTOPHER
J. M. SMITH4, RICHARD M. DE LA RUE4, HENRI BENISTY1 AND CLAUDE WEISBUCH1
1Laboratoire de Physique de la Matière
Condensée, Ecole Polytechnique, F-91128 Palaiseau, France
2School of Physics and Astronomy, University
of St Andrews, St Andrews, Fife, KY16 9SS, Scotland, United Kingdom
3Institut de Micro- et Opto-électronique,
Ecole Polytechniqe Fédérale de Lausanne, CH-1015, Lausanne,
Switzerland
4Department of Electronics and Electrical Engineering,
University of Glasgow, Glasgow G12 8LT, Scotland, United Kingdom
Abstract. The use of photonic crystals for realistic light emitting diodes is discussed, given the constraints of planar semiconductor technology. A viable route for the fabrication of high-efficiency high-brightness electrically injected light emitting diodes is presented. The starting point is a top-emitting microcavity using a single Alox Bragg mirror. The active area is surrounded by two-dimensional photonic crystals, namely arrays of air rods etched through the top layers ; injection of the electrons is achieved through the crystals. Design rules for photonic crystals as efficient out-couplers are detailed. The building blocks are assessed experimentally, and we show that promising results are at hand.
Optical and Quantum Electronics, vol.34, pp.79-89, 2002
Abstract--We present an improved version of microcavity light-emitting
diodes, relying on the use of a low-index material, aluminum oxide. Our
work addresses in particular the injection scheme required by the insulating
nature of this oxide. The device we fabricated demonstrated efficiencies
up to 28% in air, using only planar technology. In these structures, most
of the emission is guided. We further propose to include photonic
crystals to extract this guided light. The design of the photonic crystals
are discussed and substantiated by photoluminescence-based experiments.
Index Terms--High-efficiency LEDs, Microcavities, Aluminium Oxide,
Photonic Crystals, Gratings, Outcouplers
Journal of Selected Topics in Quantum Electronics, accepted, 2002
Modification of dipole emission that is due to its optical environment is calculated for planar layered structures. The layers are optically described by standard matrix techniques, and the dipole is included by using additive source terms for the electric field that depend on dipole orientation and wave polarization. These source terms also allow coupling through evanescent waves. We emphasize the applicability of this method to cases in which the power distribution into various modes is affected: dipole emission into guided modes and emission distribution into the various modes of structures that contain multilayer reflectors, such as microcavities. ©1998 Optical Society of America
Comptes rendus de l'Académie des Sciences, Tome 3, Fascicule 1, Janvier-Février 2002
Comptes rendus de l'Académie des Sciences, Tome 3, Fascicule 1, Janvier-Février 2002
Synthetic Metals, vol.116, 449, 2001
in Photonic Crystal and Light localization in the 21st Century, C.M.Soukoulis, Ed. Dordrecht,:Kluwer, 2001, pp.117-128
C.Weisbuch
La Recherche, Décembre 2000, p.18, 2000
C. Weisbuch, H. Benisty, and R. Houdre
J. Luminescence, vol. 85, pp. 271-293, 2000
J. of High Speed Electr. and Systems, vol. 10, pp. 339-354, 2000
Physica Status Solidi (b), vol. 221, pp. 93, 2000.
Phys. Stat. Sol. (b), vol. 221, pp. 93, 2000