PMID 26567917
DOI: 10.1002/chem.201503741
WoS: WOS:000368280400024
3 Citations
Résumé:

A biosensor taking advantage of the optical properties of sorted carbon nanotubes has been developed. A polyfluorene polymer bearing azido groups was synthesized and used for the selective extraction of semi-conducting nanotubes from the bulk population. The resulting polymer-decorated nanotubes were then conjugated by click-chemistry to a ligand unit (biotin), and the sensing properties of the biotinylated nanotubes were investigated by photoluminescence measurements, upon interaction with the streptavidin target.

Ref HAL: hal-01284360_v1
DOI: 10.1021/acsphotonics.5b00327
WoS: WOS:000366884600011
Exporter : BibTex | endNote
6 Citations
Résumé:

A deep-subwavelength imaging of the optical-guided modes localized in silicon microring resonators, obtained with a polarization-sensitive Fano-imaging technique, is demonstrated. We merge together near-field scanning optical microscopy and resonant forward scattering spectroscopy, leading to near-field hyperspectral imaging without the need of embedded light emitters or evanescent light coupling into the microring. The combined analysis of the observed Fano-like spectral line shapes and of the near-field intensity spatial distributions, supported by accurate numerical calculations, gives a clear discrimination between the TE and the TM modes.

Résumé:

Nanophotonics is an emerging field where researchers look for potential application of carbon nanotubes (SWNT) in the framework of silicon photonics technology, due to SWNT ability to emit, modulate and detect light in the wavelength range of silicon transparency. In this field of nanotube photonics, a first milestone was to couple light emission from SWNT into silicon waveguides [1]. Current researches focus on coupling SWNT with optical cavities, either for enhancing nanotube photoluminescence (PL) or nonlinear optical phenomena, at the nanoscale. Several works focused on the integration of carbon nanotubes with photonic cavities built on silicon-on-insulator (SOI) substrate, which is the preferential platform for photonic applications. Such work included coupling nanotubes with microdisk resonators[2], nanobeam cavity[3] or photonic crystal cavities[4]. However, these kinds of cavities could not be easily coupled to silicon waveguides, and were addressed using out-of-the-plane μ-PL configuration, hindering subsequent integration into more complex photonic devices. Building up on our previous work[5], we propose to couple carbon nanotube PL with silicon microring resonators in a fully integrated configuration, with an access waveguide[6]. PL coupled to microring mode could be collected from the access waveguide, with efficient rejection on non-resonant photons. Emission quality factor up to 8000 were observed. Moreover, this design allow for collinear excitation of SWNT through the access waveguide, leading to efficient excitation and collection of SWNT PL at different wavelength. Compare to previous designs, the requirement of an external laser source for out-of-the-plane SWNT excitation is lifted, underlining the pertinence of this approach for realistic carbon nanotube based photonic devices.

Résumé:

Nanophotonics is an emerging field where researchers look for potential application of carbon nanotubes (SWNT) in the framework of silicon photonics technology, due to SWNT ability to emit, modulate and detect light in the wavelength range of silicon transparency. In this field of nanotube photonics, a first milestone was to couple light emission from SWNT into silicon waveguides. Current researches focus on coupling SWNT with optical cavities, either for enhancing nanotube photoluminescence (PL) or nonlinear optical phenomena at the nanoscale, using microdisk resonators, or photonic crystal cavities. However, these kinds of cavities could not be easily coupled to silicon waveguides, hindering subsequent integration into more complex photonic devices. Building up on our previous work, we propose to couple SWNT PL with silicon microring resonators in a fully integrated configuration, with an acess waveguide. PL coupled to microring modes could be collected from the access waveguide, with efficient rejection on non-resonant photons. Emission quality factor up to 8000 were observed. This design allow for collinear excitation of SWNT through the access waveguide, leading to efficient excitation and collection of SWNT PL at different wavelengths. The requirement for out-of-the-plane SWNT excitation is lifted, underlining the pertinence of this approach for realistic carbon nanotube based photonic devices.

Ref HAL: hal-01207099_v1
Ref Arxiv: 1508.01004
DOI: 10.1088/0957-4484/26/34/345201
WoS: 000359079500008
Ref. & Cit.: NASA ADS
Exporter : BibTex | endNote
19 Citations
Résumé:

Single-wall carbon nanotube are considered a fascinating nanomaterial for photonic applications and are especially promising for efficient light emitter in the telecommunication wavelength range. Furthermore, their hybrid integration with silicon photonic structures makes them an ideal platform to explore the carbon nanotube instrinsic properties. Here we report on the strong photoluminescence enhancement from carbon nanotubes integrated in silicon ring resonator circuit under two pumping configurations: surface-illuminated pumping at 735 nm and collinear pumping at 1.26 {\mu}m. Extremely efficient rejection of the non-resonant photoluminescence was obtained. In the collinear approach, an emission efficiency enhancement by a factor of 26 has been demonstrated in comparison with classical pumping scheme. This demonstration pave the way for the development of integrated light source in silicon based on carbon nanotubes.

Commentaires: . Réf Journal: Nanotechnology 26 345201 (2015)

Ref HAL: hal-00005824_v1
Ref Arxiv: cond-mat/0507099
DOI: 10.1103/PhysRevB.71.195417
WoS: 000230244100112
Ref. & Cit.: NASA ADS
Exporter : BibTex | endNote
46 Citations
Résumé:

Aqueous suspensions of bundles and individual single-wall carbon nanotubes were prepared with the help of surfactants. We study the changes in the Raman spectra of the suspensions with respect to powders, and of exfoliated tubes with respect to bundles. The radial breathing modes (RBM) upshift in suspensions because of the internal pressure of the liquid. By contrast, no shift is observed in the RBM spectra after exfoliation in the suspensions. However, we demonstrate a selectivity of the exfoliation process for tubes of small diameters.

Commentaires: Soumis le 3 Décembre 2003