Exploring the benefits of surface analysis techniques to develop double multilayer transfer printing of J-Aggregates cyanine dyes by integrating L-b-L and μCp processes.

Layer-by-layer self-assembly (L-b-L assembly) makes possible to obtain polyelectrolyte multilayers (PEMs) and one of the polyelectrolytes could be replaced by a dye molecule to obtain multilayers which may exhibit optical properties of great interest. On the other hand, μCp has become a routine technique for the preparation of micro- and nanostructured surfaces. In our development in progress of a surface engineering strategy to transfer J-Agg cyanine dyes onto surfaces by integrating L-b-L process and μCp, this contribution highlights how surface analysis imaging techniques can bring valuable information for the development of the process involving a double Multilayers Transfer Printing (MTP) with a Moiré effect.

SiN half-etch horizontal slot waveguides for integrated photonics: numerical modeling, fabrication, and characterization of passive components.

This work presents a "half-etch" horizontal slot waveguide design based on SiN, where only the upper SiN layer is etched to form a strip that confines the mode laterally. The numerical modeling, fabrication, and characterization of passive waveguiding components are described. This novel slot waveguide structure was designed with on-chip light amplification in mind, for example with an Er-doped oxide spacer layer.

Rare-earth doped micro-emitters made by lift-off processing in pulsed laser deposited layers on Si substrate.

Rare earth emitters are promising in integrated optics but require complex integration on silicon. In this work, we have fabricated an YO:Eu micro-emitter on SiO on Si substrate without etching. Since pulsed laser deposition produces a high quality layer at room temperature, material can be locally deposited on top of substrates by lift-off processing.

Selective grating obtained by dye microstructuration based on local photobleaching using a laser writer.

We propose a method to pattern organic optically active materials based on local photobleaching for creating a wavelength-selective grating. Usually, photobleaching is considered a limitation for an organic emitter. Here, this property is exploited to locally suppress dye emission and absorption at the microscale with an abrupt interface and no changes in layer thickness.

Tensile strained germanium nanowires measured by photocurrent spectroscopy and X-ray microdiffraction.

Applying tensile strain in a single germanium crystal is a very promising way to tune its bandstructure and turn it into a direct band gap semiconductor. In this work, we stress vapor-liquid-solid grown germanium nanowires along their [111] axis thanks to the strain tranfer from a silicon nitride thin film by a microfabrication process. We measure the Γ-LH direct band gap transition by photocurrent spectrometry and quantify associated strain by X-ray Laue microdiffraction on beamline BM32 at the European Synchrotron Radiation Facility.

The micropatterning of layers of colloidal quantum dots with inorganic ligands using selective wet etching.

The micropatterning of layers of colloidal quantum dots (QDs) stabilized by inorganic ligands is demonstrated using PbS core and CdSe/CdS core/shell QDs. A layer-by-layer approach is used to assemble the QD films, where each cycle involves the deposition of a QD layer by dip-coating, and the replacement of the native organic ligands by inorganic moieties, such as OH(-) and S(2-), followed by a thorough cleaning of the resulting film. This results in a smooth and crack-free QD film on which a photoresist can be spun.

Study of evanescently-coupled and grating-assisted GaInAsSb photodiodes integrated on a silicon photonic chip.

In this paper we present GaInAsSb photodiodes heterogeneously integrated on SOI by BCB adhesive bonding for operation in the short-wave infrared wavelength region. Photodiodes using evanescent coupling between the silicon waveguide and the III-V structure are presented, showing a room temperature responsivity of 1.4A/W at 2.