Publications by Ulagalandha Perumal Dharanipathy

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

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

On the investigation of light-matter interactions in slab photonic crystal cavities

Ulagalandha Perumal Dharanipathy

EPFL2014

High-Q silicon photonic crystal cavity for enhanced optical nonlinearities

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

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

Romuald Houdré, Nicolas Maxime André Descharmes, Ulagalandha Perumal Dharanipathy, Zhaolu Diao, 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

Single particle detection, manipulation and analysis with resonant optical trapping in photonic crystals

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

We demonstrate a resonant optical trapping mechanism based on two-dimensional hollow photonic crystal cavities. This approach benefits simultaneously from the resonant nature and unprecedented field overlap with the trapped specimen. The photonic crystal s ...

Royal Society of Chemistry2013

Self-trapping and back-action effects in hollow photonic crystal cavity optical trap

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

We report on the first experimental demonstration of resonant optical trapping of dielectric particles in a two-dimensional hollow photonic crystal cavity. The cavities are implemented in an optofluidic chip consisting of a silicon-on-insulator substrate a ...

Spie-Int Soc Optical Engineering2013

High quality factor two dimensional GaN photonic crystal cavity membranes grown on silicon substrate

Nicolas Grandjean, Romuald Houdré, Jean-François Carlin, Raphaël Butté, Jacques Levrat, Antonino Francesco Castiglia, Kirill Atlasov, Georg Rossbach, Noelia Vico Triviño, Ulagalandha Perumal Dharanipathy

We report on the achievement of freestanding GaN photonic crystal L7 nanocavities with embedded InGaN/GaN quantum wells grown by metal organic vapor phase epitaxy on Si (111). GaN was patterned by e-beam lithography, using a SiO2 layer as a hard mask, and ...

American Institute of Physics2012

Near-infrared characterization of gallium nitride photonic-crystal waveguides and cavities

Nicolas Grandjean, Romuald Houdré, Jean-François Carlin, Noelia Vico Triviño, Ulagalandha Perumal Dharanipathy, Zhaolu Diao

We report the design and optical characterization of fully suspended wire waveguides and photonic crystal (PhC) membranes fabricated on a gallium nitride layer grown on silicon substrate operating at 1.5 mu m. W1-type PhC waveguides are coupled with suspen ...

Optical Society of America2012

Microfluidic integrated hollow photonic crystal cavities for single particle and resonant field interaction

Romuald Houdré, Nicolas Maxime André Descharmes, Ulagalandha Perumal Dharanipathy, Zhaolu Diao

A microfluidic-integrated single particle sensor based on hollow photonic crystal cavities is reported. The interaction relies on the reversible resonance frequency shift induced by a dielectric particle near the cavity. ...

Ieee2012