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Romuald Houdré

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Related publications (102)

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Statistics of the disorder-induced losses of high-Q photonic crystal cavities

Romuald Houdré, Vincenzo Savona, Momchil Minkov, Ulagalandha Perumal Dharanipathy

We analyze and compare the effect of fabrication disorder on the quality factor of six well-known high-index photonic crystal cavity designs. The theoretical quality factors for the different nominal structures span more than three orders of magnitude, ran ...

Optical Society of America2013

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

Optical Trapping and Fast Discrimination of Label-Free Bacteriophages at the Single Virion Level

Romuald Houdré, Nicolas Villa, Enrico Tartari

There is a recent resurgence of interest in phage therapy (the therapeutic use of bacterial viruses) as an approach to eliminating difficult-to-treat infections. However, existing approaches for therapeutic phage selection and virulence testing are time-co ...

Wiley-V C H Verlag Gmbh2024

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

Observation of Backaction and Self-Induced Trapping in a Planar Hollow Photonic Crystal Cavity

Romuald Houdré, Nicolas Maxime André Descharmes, Zhaolu Diao, Ulagalandha Perumal Dharanipathy, Mario Lucien Henri Tonin

The optomechanical coupling between a resonant optical field and a nanoparticle through trapping forces is demonstrated. Resonant optical trapping, when achieved in a hollow photonic crystal cavity is accompanied by cavity backaction effects that result fr ...

American Physical Society2013

Inhibited emission of electromagnetic modes confined in subwavelength cavities

Romuald Houdré, Nicolas Le Thomas

We experimentally demonstrate the active inhibition of subwavelength confined cavity modes emission and quality factor enhancement by controlling the cavity optical surrounding. The intrinsic radiation angular spectrum of modes confined in planar photonics ...

2011

Complex-coupled photonic crystal THz lasers with independent loss and refractive index modulation

Romuald Houdré, Hua Zhang

Compared to near infra-red photonic crystal (PhC) band-edge lasers, achieving vertical emission with quantum cascade (QC) material operating in the THz range needs dedicated engineering because the TM polarized emission of QCLs favors in-plane emitting sch ...

2011

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

Design and fabrication technology for high performance electrical pumped terahertz photonic crystal band edge lasers with complete photonic band gap

Romuald Houdré, Hua Zhang

We detail the design and fabrication technology of two-dimensional photonic crystal (PhC) band edge emitting quantum cascade lasers (QCLs) operating at terahertz frequencies (similar to 3.3 THz). The entire QCL active layer has been deeply etched to form a ...

2010

Quantum fluid properties of polaritons in semiconductor microcavities

Romuald Houdré, Cristiano Ciuti

In semiconductor quantum wells embedded in a high finesse microcavity, excitons, which are bound electron-hole systems, strongly couple to photons, forming mixed quasi-particles called polaritons. Polaritons can be coherently excited by an incident laser f ...

2010

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

Romuald Houdré, Nicolas Le Thomas, Laurent Balet

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

Finite-Size and Disorder Effects on Slow-Light Propagation in an Extended Photonic Crystal Coupled-Cavity Waveguides with Group-Index Bandwidth Product Exceeding 0.47

Romuald Houdré, Vincenzo Savona, Momchil Minkov, Mohamed Sabry Abdel-Aliem Mohamed

IEEE2018

On-Chip Optical Nanotweezers for Ultrafast Antibiotic and Bacteriophage Susceptibility Testing

Romuald Houdré, Nicolas Villa, Enrico Tartari

Rapid analysis of antimicrobial susceptibility is a challenge in the fight against infectious diseases. Here we report how the interaction between integrated optical tweezers and bacteria reveals antibiotic- and bacteriophage-induced physiological stresses ...

Optical Society of America2023

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

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

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

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

Hybrid PDMS/glass microfluidics for high resolution imaging and application to sub-wavelength particle trapping

Romuald Houdré, Nicolas Maxime André Descharmes, Mario Lucien Henri Tonin

We demonstrate the fabrication of a hybrid PDMS/glass microfluidic layer that can be placed on top of non-transparent samples and allows high-resolution optical microscopy through it. The layer mimics a glass coverslip to limit optical aberrations and can ...

Royal Society of Chemistry2016

Refractive index sensing with an air-slot photonic crystal nanocavity

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

We investigate an air-slot photonic crystal cavity for high-precision refractive index sensing. The high quality factor ∼2:6 × 10^4 of the cavity, along with a strong overlap between the resonant mode and the hollow core region, allows us to achieve an exp ...

Optical Society of America2010

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

Planar photonic crystals infiltrated with liquid crystals: optical characterization of molecule orientation

Romuald Houdré, Rolando Ferrini, Libero Zuppiroli, Liza Carol Andrea Dunbar, Barbara Wild, Vasily Zabelin

Nematic liquid crystals are infiltrated into InP-based planar photonic crystals. Optical measurements as a function of temperature and polarization are used to study the average director field configuration in the nanometer-size holes: a planar equilibrium ...

Opt. Soc. America2006

Feature size effects in chemically assisted ion beam etching of InP-based photonic crystals

Romuald Houdré, Rolando Ferrini

This work addresses feature size effects (the lag-effect and roughness development) in chemically assisted ion beam etching (CAIBE) etching of InP-based photonic crystals. Photonic crystal fields with varying hole size and periods were etched with differen ...

International Society for Optical Engineering, Bellingham WA, WA 98227-0010, United States2006