Publications de Davide Grassani

Design rules for frequency conversion in periodically poled thin film lithium niobate waveguides

Camille Sophie Brès, Davide Grassani, Hamed Sattari, Nikolay Balakleyskiy, Christian André Clément Lafforgue, Yesim Koyaz

SPIE Society of Photo-Optical Instrumentation Engineers2024

Supercontinuum in integrated photonics: generation, applications, challenges and perspectives (vol 12, pg 1199, 2023) [Erratum]

Camille Sophie Brès, Victor Brasch, Davide Grassani

2023

Unconventional time-bandwidth performance of resonant cavities with nonreciprocal coupling

Camille Sophie Brès, Davide Grassani, Ivan Cardea, Kosmas Tsakmakidis

The time-bandwidth limit is a mathematical tenet that affects all reciprocal resonators, stating that the product of the spectral bandwidth that can couple into a resonant system and its characteristic energy decay time is always equal to 1. Here, we devel ...

2021

Tailored on-chip mid-IR light generation and application for gas spectroscopy

Camille Sophie Brès, Davide Grassani, Eirini Tagkoudi

In this contribution, we present how coherent supercontinuum generation in Si3N4 waveguides enabled by fiber laser pumping can be tailored to cover part of the mid-IR spectrum and the use of such sources in spectroscopy. ...

2021

Multi-gas spectroscopy using tailored mid-IR dispersive wave generated in Si3N4 waveguide

Camille Sophie Brès, Davide Grassani, Eirini Tagkoudi

We demonstrate simultaneous detection of acetylene, methane and ethane using milliwatt-level dispersive-wave generated in a Si3N4 waveguide covering 2900 cm-1-3380 cm-1 spectral region. This simple mid-IR absorption spectroscopy scheme achieves hundreds of ...

2021

Formation Rules and Dynamics of Photoinduced χ(2) Gratings in Silicon Nitride Waveguides

Tobias Kippenberg, Martin Hubert Peter Pfeiffer, Camille Sophie Brès, Davide Grassani, Edgars Nitiss, Tianyi Liu

Silicon nitride has emerged as a prominent platform for building photonics integrated circuits. While its nonlinear properties based on third-order effects have been successfully exploited, an efficient second harmonic generation in standard stoichiometric ...

2020

Parallel gas spectroscopy using mid-infrared supercontinuum from a single Si3N4 waveguide

Tobias Kippenberg, Camille Sophie Brès, Davide Grassani, Clemens Herkommer, Eirini Tagkoudi

Efficient third-order nonlinear optical processes have been successfully integrated on silicon nitride (Si3N4) waveguides. In particular, owing to Si3N4 wide transparency window spanning from the visible to the middle-infrared (mid-IR), efficient mid-IR di ...

2020

Arbitrarily high time bandwidth performance in a nonreciprocal optical resonator with broken time invariance

Camille Sophie Brès, Hatice Altug, Davide Grassani, Simon Julien Fabbri, Ivan Cardea, Kosmas Tsakmakidis

Most present-day resonant systems, throughout physics and engineering, are characterized by a strict time-reversal symmetry between the rates of energy coupled in and out of the system, which leads to a trade-off between how long a wave can be stored in th ...

Nature Research2020

Mid infrared gas spectroscopy using efficient fiber laser driven photonic chip-based supercontinuum

Tobias Kippenberg, Camille Sophie Brès, Hairun Guo, Davide Grassani, Clemens Herkommer, Eirini Tagkoudi

Directly accessing the middle infrared, the molecular functional group spectral region, via supercontinuum generation processes based on turn-key fiber lasers offers the undeniable advantage of simplicity and robustness. Recently, the assessment of the coh ...

Nature Research2019

Second- and third-order nonlinear wavelength conversion in an all-optically poled Si3N4 waveguide

Tobias Kippenberg, Martin Hubert Peter Pfeiffer, Camille Sophie Brès, Davide Grassani

Silicon nitride (Si3N4) is commonly employed to integrate third-order nonlinear optical processes on a chip. Its amorphous state, however, inhibits significant second-order nonlinear response. Recently, second-harmonic generation enhancement has been obser ...

2019

Optically Probed Time Dynamics of χ(2) Grating Inscription in SiN Waveguides

Tobias Kippenberg, Camille Sophie Brès, Davide Grassani, Edgars Nitiss, Tianyi Liu

Silicon Nitride (S13N4) waveguide platforms have seen significant interest in the recent years, motivated by several advantageous properties such as compatibility with CMOS fabrication standards, low propagation loss, high refractive index and optical nonl ...

2019

Gas spectroscopy using low threshold mid-infrared radiation generated in Si3N4 waveguides

Tobias Kippenberg, Camille Sophie Brès, Hairun Guo, Davide Grassani, Eirini Tagkoudi

We report trace-gas absorption spectroscopy based on the efficient generation of a 3.05μm dispersive wave in a Si3N4 waveguide pumped by a 2.09 μm femtosecond mode-locked fiber laser ...

OSA Publishing2019

Mid-infrared frequency comb via coherent dispersive wave generation in silicon nitride nanophotonic waveguides

Tobias Kippenberg, Martin Hubert Peter Pfeiffer, Camille Sophie Brès, Adrien Billat, Hairun Guo, Davide Grassani, Clemens Herkommer, Chuankun Zhang, Wenle Weng

Mid-infrared optical frequency combs are of significant interest for molecular spectroscopy due to the large absorption of molecular vibrational modes on the one hand, and the ability to implement superior comb-based spectroscopic modalities with increased ...

Nature Publishing Group2018

Efficient mid-infrared dispersive wave generation in dispersion-engineered Si3N4 waveguides pumped at 2 μm

Tobias Kippenberg, Camille Sophie Brès, Hairun Guo, Davide Grassani, Clemens Herkommer, Eirini Tagkoudi

We demonstrate efficient generation of mid-infrared dispersive wave at 3.5 m in a Si3N4 waveguide pumped by a 2090nm femtosecond mode-locked fiber laser. The 8% maximum efficiency allows for a milliwatt-level average power mid-infrared pulse. ...

2018

Observation of Second Harmonic and Sum Frequency in an Optically Poled Si3N4 Waveguide

Tobias Kippenberg, Martin Hubert Peter Pfeiffer, Camille Sophie Brès, Adrien Billat, Davide Grassani

Enhanced second order nonlinear processes in a Si3N4 waveguide following optically induced χ(2) is demonstrated, enabling the detection of a frequency doubled pulsed train and SFG with >-37 dB conversion efficiency for 18 W pump peak power. ...

2018

Overcoming the time-bandwidth limit

Camille Sophie Brès, Davide Grassani, Simon Julien Fabbri, Ivan Cardea, Kosmas Tsakmakidis

We are so accustomed to the time-bandwidth limit that we often take it to be a fundamental relation that cannot be overcome. Contrary to this belief we here propose that the storage/delay time of a system can in fact be decoupled from the operating bandwid ...

IEEE2018

Enhancing Optical Nonlinear Processes Performance of Silicon Nitride Waveguides

Camille Sophie Brès, Davide Grassani, Eirini Tagkoudi

Silicon nitride has recently attracted significant interest for nonlinear integrated optics. In addition to its excellent linear properties, silicon nitride offers a bandgap larger than silicon, and a wide transparency window spanning from the visible all ...

IEEE2018

Mid-infrared continuous-wave parametric amplification in chalcogenide microstructured fibers

Camille Sophie Brès, Svyatoslav Kharitonov, Davide Grassani, Sida Xing

The persistent growth of interest in the middle infrared (MIR) is stimulating the development of sources and components. Novel waveguides and fibers for the efficient use of nonlinear effects in the MIR are being intensively studied. Highly nonlinear silic ...

2017

MIR supercontinuum in all-normal dispersion Chalcogenide photonic crystal fibers pumped with 2μm femtosecond laser

Camille Sophie Brès, Svyatoslav Kharitonov, Davide Grassani, Sida Xing, Jianqi Hu

We demonstrate mid-infrared supercontinuum generation in an all-normal dispersion Chalcogenide PCF pumped by fiber laser. The -20dB bandwidth is 1.7~2.7μm dominated by self-phase modulation and optical wave breaking. Tapering is proposed to improve perform ...

OSA2017

Narrow linewidth polarizer-free 2.1μm Ho-doped fiber laser with 45dB polarization extinction ratio

Camille Sophie Brès, Davide Grassani, Sida Xing

2017