Adrien Billat

High-power parametric conversion from near-infrared to short-wave infrared

We report the design of an all-fiber continuous wave Short-Wave Infrared source capable to output up to 700 mW of power at 1940 nm. The source is tunable over wavelength intervals comprised between 1850 nm and 2070 nm depending on its configuration. The output can be single or multimode while the optical signal to noise ratio ranges from 25 and 40 dB. The architecture is based on the integrated association of a fiber optical parametric amplifier and a Thulium doped fiber amplifier.

Characterization and modeling of microstructured chalcogenide fibers for efficient mid-infrared wavelength conversion

We experimentally demonstrate wavelength conversion in the 2 µm region by four-wave mixing in an AsSe and a GeAsSe chalcogenide photonic crystal fibers. A maximum conversion efficiency of -25.4 dB is measured for 112 mW of coupled continuous wave pump in a 27 cm long fiber. We estimate the dispersion parameters and the nonlinear refractive indexes of the chalcogenide PCFs, establishing a good agreement with the values expected from simulations. The different fiber geometries and glass compositions are compared in terms of performance, showing that GeAsSe is a more suited candidate for nonlinear optics at 2 µm. Building from the fitted parameters we then propose a new tapered GeAsSe PCF geometry to tailor the waveguide dispersion and lower the zero dispersion wavelength (ZDW) closer to the 2 µm pump wavelength. Numerical simulations shows that the new design allows both an increased conversion efficiency and bandwidth, and the generation of idler waves further in the mid-IR regions, by tuning the pump wavelength in the vicinity of the fiber ZDW.

Broadly tunable source around 2050 nm based on wideband parametric conversion and thulium–holmium amplification cascade

We report the design of a short-wave infrared continuous-wave light source featuring a 20 mW average output power, and with a wavelength that can be freely selected in the 2000-2100 nm range amid a low power ripple. The operating principle relies on the simultaneous broadband parametric conversion of two seeds in a highly nonlinear silica fiber pumped in the L-band followed by amplification and equalization in an appended thulium- and holmium- doped fiber cascade directly pumped by their respective previous stage.

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

Clemens Herkommer, 2, ∗ Adrien Billat, ∗ Hairun Guo, ∗ Davide Grassani, Chuankun Zhang, 4 Martin H. P. Pfeiffer, Camille-Sophie Brès, † and Tobias J. Kippenberg ‡ École Polytechnique Fédérale de Lausanne (EPFL), LPQM, CH-1015 Lausanne, Switzerland Technische Universität München (TUM), Physik-Department, D-80333 München, Germany École Polytechnique Fédérale de Lausanne (EPFL), PHOSL, CH-1015 Lausanne, Switzerland Tsinghua University, Beijing 100084, China

Versatile High Repetition Rate 2-μm Pulsed Source Based on Wideband Parametric Conversion

We report an all-fiber pulsed source based on parametric conversion followed by thulium amplification able to deliver picosecond pulses at a repetition rate selectable between 2 and 5 GHz, of which central wavelength can be freely selected in the 2-μm region. A very versatile Nyquist pulse shaping of the parametric pump, which allows for the electrical control of the pulse train, enables such a freedom in the repetition rate selection, as well as some control in the pulse duration. We also show that data can be embedded in the output pulse train resulting in a high-quality Gb/s return-to-zero transmitter. Such a programmable short-wave infrared laser is of high interest for sensing or nonlinear optics applications around 2000 nm that require a fine adjustment in both the spectral and temporal domains.

Tunable Thulium-Assisted Parametric Generation of 10 Gb/s Intensity Modulated Signals Near 2 μm

We report the demonstration of an all-fiber 10Gb/s modulation capable source near 2μm, tunable over more than 60nm with powers exceeding 2dBm, based on parametric conversion and appended Thulium amplification.

A chip-based silicon nitride platform for mid-infrared nonlinear photonics

We developed a chip-based silicon nitride platform with thick waveguides (> 2 μm) that overcomes the usual fabrication limitation. We demonstrate both microresonator frequency comb generation at 2.5 μm and supercontinuum generation extending beyond 4.0 μm in this platform.

Widely tunable picosecond-pulsed source near 2 μm based on cascaded Raman wavelength shifting

We demonstrate a cavity-less picosecond pulsed source near 2μm, tunable over more than 200nm based on third order cascaded Raman wavelength shifting. Up to 40% conversion is achieved for 100mW peak powers at 200 MHz repetition rate.

Thulium Assisted Parametric Conversion from Near to Short Wave Infrared

We report an all-fiber continuous wave source, tunable between 1935-1980nm, based on parametric conversion combined with thulium amplification. More than 150mW of power and 30dB optical signal-to-noise ratio is obtained over the entire range.

Recent advances on nonlinear optics in Silicon Nitride waveguides

Nonlinear phenomena based on the material 2nd or 3rd order nonlinear susceptibility tensor χ(2) and χ(3), respectively, offer potential in a wide variety of applications by exploiting wave-mixing capabilities. The integration of these nonlinear effects at the chip scale represents the best path towards portable, compact and low power optical signal processing devices. A significant body of work has been done recently in this direction, in particular focusing on CMOS-compatible platforms. While many nonlinear effects have been demonstrated in Silicon, Silicon Nitride has recently sparked significant interest. Owing to a larger band gap, wide transparency window and low loss, the potential of SiN waveguides for linear and nonlinear optics is now well established. In this paper, we report recent results on nonlinear processes in SiN waveguides. In particular we will cover generation of an extremely broad supercontinuum extending 400 THz from the visible to 3.6 µm pumped by a turnkey telecom wavelength pulsed source. We will also report on a tunable pulse source based on dispersive wave generation in an engineered thick waveguide. Finally, we will show that SiN offers some interesting potential for χ(2) based nonlinear effects, an important step towards integrating second order nonlinearity on chip.