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Romuald Houdré

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Publications associées (102)

Exciton-polariton spin switches

Romuald Houdré, Timothy Chi Hin Liew

Integrated switching devices comprise the building blocks of ultrafast optical signal processing(1,2). As the next stage following intensity switching(1,3,4), circular polarization switches(5-9) are attracting considerable interest because of their applica ...

Nature Publishing Group2010

Light engineering of the polariton landscape in semiconductor microcavities

Romuald Houdré, Cristiano Ciuti

We demonstrate a method to create potential barriers with polarized light beams for polaritons in semiconductor microcavities. The form of the barriers is engineered via the real space shape of a focalized beam on the sample. Their height can be determined ...

2010

Group velocity and energy transport velocity near the band edge of a disordered coupled cavity waveguide: an analytical approach

Romuald Houdré

We develop an analytical approach to theoretically investigate light speed propagation near the band edge of a coupled cavity waveguide in the presence of residual disorder. This approach that is based on a mean field theory allows us to define the domains ...

Optical Society of America2010

Fourier space imaging of light localization at a photonic band-edge located below the light cone

Romuald Houdré, Nicolas Le Thomas

We observe light localization in a two-dimensional geometry, induced by residual disorder at a photonic band edge located below the light cone. The combination of a spectrally selective illumination and a grating assisted k-space imaging technique allows u ...

2009

Theoretical Investigation of the Radiation Pattern From LEDs Incorporating Shallow Photonic Crystals

Romuald Houdré

A theoretical approach based on coupled-mode theory is presented in order to determine the radiation pattern of LEDs incorporating a shallow photonic crystal. From this, a fundamental limit for the directionality of the diffraction of a single guided mode ...

2009

Superfluidity of polaritons in semiconductor microcavities

Romuald Houdré, Cristiano Ciuti

Superfluidity, the ability of a quantum fluid to flow without friction, is one of the most spectacular phenomena occurring in degenerate gases of interacting bosons. Since its first discovery in liquid helium-4 (refs 1, 2), superfluidity has been observed ...

Nature Publishing Group2009

Radiation loss of photonic crystal coupled-cavity waveguides

Romuald Houdré, Nicolas Le Thomas, Hua Zhang, Jana Jágerská

We experimentally investigate the out-of-plane radiation losses of photonic crystal coupled-cavity waveguides. We observe a strong variation in the losses along the dispersion curve and show that such variation is closely linked with the specific far-field ...

American Institute of Physics2009

Experimental observation of slow mode dispersion in photonic crystal coupled-cavity waveguides

Romuald Houdré, Roel Baets, Nicolas Le Thomas, Vasily Zabelin, Jana Jágerská

We experimentally investigate the dispersion curve of an integrated silicon-on-insulator coupled-cavity waveguide in a photonic crystal environment using a technique based on far-field imaging. We show that a chain of eight coupled cavities of a moderate Q ...

Optical Society of America2009

Bloch mode excitation in two-dimensional photonic crystals imaged by Fourier optics

Romuald Houdré, Nicolas Le Thomas

Coupling into the Bloch modes of a two-dimensional photonic crystal (PhC) field is investigated by Fourier optics. The PhC was designed to operate in the second band above the air-light line, close to the autocollimation regime for TE polarization. The sam ...

2009

Terahertz Quantum Cascade Lasers based on two-dimensional photonic crystal resonators

Romuald Houdré, Marcella Giovannini, Lorenzo Sirigu, Jérôme Faist

We demonstrate high spectral control from surface emitting THz Quantum Cascade Lasers based on a two-dimensional photonic crystal cavity. The perforated top metallic contact acts as an in plane resonator in a tight double-metal plasmonic waveguide providin ...

2008

Local infiltration of planar photonic crystals with UV-curable polymers

Romuald Houdré, Libero Zuppiroli, Rolando Ferrini, Laurent Balet, Pascale El-Kallassi

We present the local polymer infiltration of planar photonic crystal cavities via a maskless laser-writing technique. After the infiltration of the air holes with a UV-curable monomer a focused laser is used to locally polymerize the monomer in selected ho ...

2008

Impact of feature-size dependent etching on the optical properties of photonic crystal devices

Romuald Houdré, Rolando Ferrini

Feature size dependence in Ar/Cl2 chemically assisted ion beam etching of InP-based photonic crystals (PhCs) and its influence on the optical properties of PhC devices operating in the band gap are investigated. The analysis of the measured quality factors ...

2008

Spectral tuning and near-field imaging of photonic crystal microcavities

Romuald Houdré, Carl Zinoni, Massimo Gurioli, Laurent Balet

We experimentally observe a sizable and reversible spectral tuning of the resonances of a two-dimensional photonic crystal microcavity induced by the introduction of a subwavelength size glass tip. The comparison between experimental near-field data, colle ...

2008

Coupling length of silicon-on-insulator directional couplers probed by Fourier-space imaging

Romuald Houdré, Nicolas Le Thomas, Jana Jágerská

We use a Fourier-space imaging technique relying on outcoupling grating probes to study the coupled mode interaction and dispersion properties of guided modes in silicon-on-insulator codirectional couplers. Our approach allows us to measure the mode splitt ...

American Institute of Physics2008

Influence of residual disorder on the anticrossing of Bloch modes probed in k space

Romuald Houdré, Nicolas Le Thomas, Vasily Zabelin

We retrieve the dispersion properties of photonic crystal waveguides near the band edge with high experimental accuracy. The dispersion diagram of the waveguide modes in the complex-valued plane is directly measured in the far ﬁeld by using a Fourier space ...

2008

Near-field mapping of quantum dot emission from single-photonic crystal cavity modes

Romuald Houdré, Massimo Gurioli, Laurent Balet, Nicolas Le Thomas

We directly investigate, by means of near-field spectroscopy, the spatial distribution of the optical cavity modes of 2D photonic crystal microcavities. Numerical simulations confirm that the photoluminescence maps of quantum dots embedded in the photonic ...

2008

Local tuning of the optical response of two-dimensional photonic crystals

Romuald Houdré, Libero Zuppiroli, Rolando Ferrini, Laurent Balet, Pascale El-Kallassi

Local tuning of the optical response of GaAs-based two dimensional photonic crystals (PhCs) is reported. A selective polymer infiltration technique was developed. Scanning electron microscopy and optical measurements were used to characterize the filled Ph ...

Eindhoven University of Technology2008

Hybrid inorganic-organic photonic devices

Romuald Houdré, Libero Zuppiroli, Rolando Ferrini, Laurent Balet, Nicolas Le Thomas, Pascale El-Kallassi

We present the infiltration of semiconductor photonic devices with organic materials. The infiltration procedures are described and validated. In particular, the optical properties of hybrid photonic crystal cavities are studied. ...

EOS2008

Characterisation of photonic crystal and nanophotonics devices with Fourier optics

Romuald Houdré, Nicolas Le Thomas, Jana Jágerská

We report on the experimental investigation of the Floquet-Bloch modes propagation inside photonic crystal (PhC) structures as well as their emission from the structures with far-field optics. We demonstrate that far-field optical experiments can be used t ...

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2008

Towards a LED based on a photonic crystal nanocavity for single photon sources at telecom wavelength

Romuald Houdré, Blandine Alloing, Carl Zinoni, Laurent Balet, Nicolas Le Thomas

A fundamental step towards achieving an "on demand" single photon source would be the possibility of electrical pumping for a single QD and thus the integration of such a device in an opto-electronic circuit. In this work we describe the fabrication proces ...

Elsevier2008

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