Publications de Romuald Houdré

Si and III-nitride based photonic crystal cavities for optical trapping and non-linear optics

The project data will be organised in the following folder system : One main folder for the each subproject : GaN nonlinear optics and Optical trapping Each folder is organised in the following sub-folder system (not all may be used), each with a readme- ...

Zenodo2025

Monitoring of Single-Cell Bacterial Lysis by Phages Within Integrated Optical Traps

Romuald Houdré, Nicolas Villa

The bacterial ecosystem is naturally balanced by viruses known as bacteriophages. Accordingly, they represent an emerging adjuvant to antibiotics to fight bacterial infections. However, the interaction of a single bacterium with bacteriophages remains poor ...

WILEY-V C H VERLAG GMBH2025

On-Chip Optical Trapping Enabling Real-Time Monitoring of Phage-Bacterium Interaction

Romuald Houdré, Nicolas Villa

bacteriophages are viruses sought after to fight bacterial antimicrobial resistance. Here we demonstrate that on-chip optical trapping allows observing the bacterial lysis of a phage infected single bacterium without any needs of labelling or bioreceptors. ...

Optical Society of America2025

Strain engineering and strain measurement by spring tethers on suspended epitaxial GaN-on-Si photonic crystal devices

Romuald Houdré, Jun Wang

Suspended epitaxial gallium nitride (GaN) on silicon (Si) photonic crystal devices suffer from large residual tensile strain, especially for long waveguides, because fine structures tend to crack due to large stress. By introducing spring-like tethers, des ...

Iop Publishing Ltd2024

Photonic Crystal Cavities for Ultrafast Antimicrobial Susceptibility Testing at the Single-Bacterium Level

Romuald Houdré, Nicolas Villa

Antimicrobial resistance poses a significant threat to human health. The resistance arises from factors such as natural bacterial mutations and the widespread misuse of antibiotics in both agronomical and medical practices. Traditional antimicrobial suscep ...

Institute of Electrical and Electronics Engineers Inc.2024

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

Romuald Houdré, Nicolas Villa

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

Integrated photonic crystal nanotweezers for bacteria and bacteriophages viruses trapping and susceptibility testing

Romuald Houdré

IEEE2024

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

Romuald Houdré, Nicolas Villa

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

Efficient second harmonic generation in a doubly resonant photonic crystal cavity based on a bound state in the continuum

Jean-François Carlin, Romuald Houdré, Nicolas Grandjean, Matteo Galli, Jun Wang

Making use of bound states in the continuum, we present experimental results on efficient second harmonic generation in photonic crystal cavities supporting doubly-resonant modes. The second harmonic emission is a vortex beam with radial polarization and e ...

IEEE2020

Doubly resonant second-harmonic generation of a vortex beam from a bound state in the continuum

Jean-François Carlin, Romuald Houdré, Nicolas Grandjean, Matteo Galli, Momchil Minkov, Jun Wang, Marco Clementi

Second-harmonic generation in nonlinear materials can be greatly enhanced by realizing doubly resonant cavities with high quality factors. However, fulfilling such doubly resonant condition in photonic crystal (PhC) slab cavities is a long-standing challen ...

2020

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

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

IEEE2018

Ultra-wide-band structural slow light

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

The ability of using integrated photonics to scale multiple optical components on a single monolithic chip offers key advantages to create miniature light-controlling chips. Numerous scaled optical components have been already demonstrated. However, presen ...

Nature Research2018

Influence of Disorder and Finite-Size Effects on Slow Light Transport in Extended Photonic Crystal Coupled-Cavity Waveguides

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

A convenient approach for slowing down light in integrated optical circuits is by utilizing a set of coupled microcavities in a photonic crystal lattice. While this provides for flexibility in dispersion engineering, light transport is influenced by a comb ...

2018

Gram-type differentiation of bacteria with 2D hollow photonic crystal cavities

Romuald Houdré, El Hadji Malick Camara, Rita Therisod

Fast and label-free techniques to analyze viruses and bacteria are of crucial interest in biological and bio-medical applications. For this purpose, optofluidic systems based on the integration of photonic structures with microfluidic layers were shown to ...

2018

Efficient continuous-wave nonlinear frequency conversion in high-Q gallium nitride photonic crystal cavities on silicon

Vincenzo Savona, Jean-François Carlin, Romuald Houdré, Nicolas Grandjean, Matteo Galli, Momchil Minkov, Mohamed Sabry Abdel-Aliem Mohamed

We report on nonlinear frequency conversion from the telecom range via second harmonic generation (SHG) and third harmonic generation (THG) in suspended gallium nitride slab photonic crystal (PhC) cavities on silicon, under continuous-wave resonant excitat ...

2017

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

Global Optimization of Ultrahigh-Q H0 Photonic Crystal Nanocavity in Silicon

Vincenzo Savona, Romuald Houdré, Ulagalandha Perumal Dharanipathy, Momchil Minkov, Mario Lucien Henri Tonin

The design of photonic crystal cavities has always presented a considerable challenge over the past two decades. In this work, a global optimization technique has been used to maximize the Q/V ratio of a simple H0 type nanocavity. The optimization is carri ...

Ieee2014

High-Q silicon photonic crystal cavity for enhanced optical nonlinearities

Vincenzo Savona, Romuald Houdré, Ulagalandha Perumal Dharanipathy, Momchil Minkov, Mario Lucien Henri Tonin

We fabricate and experimentally characterize an H0 photonic crystal slab nanocavity with a design optimized for maximal quality factor, Q = 1.7 x 10(6). The cavity, fabricated from a silicon slab, has a resonant mode at lambda = 1.59 mu m and a measured Q- ...

American Institute of Physics2014

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

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

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

Continuous-wave vertically emitting photonic crystal terahertz laser

Romuald Houdré, Jérôme Faist, Christopher Bonzon, Zhaolu Diao

Compact semiconductor light sources with high performance continuous-wave (CW) and single mode operation are highly demanded for many applications in the terahertz (THz) frequency range. Distributed feedback (DFB) and photonic crystal (PhC) quantum cascade ...

Wiley-VCH Verlag Berlin2013