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Keyvaninia S.,Ghent University | Keyvaninia S.,Center for Nano and Biophotonics Photonics | Verstuyft S.,Ghent University | Verstuyft S.,Center for Nano and Biophotonics Photonics | And 14 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013

In this paper we show that using a DVS-BCB adhesive bonding process compact heterogeneously integrated III-V/silicon single mode lasers can be realized. Two new designs were implemented: in a first design a multimode interferometer coupler (MMI) - ring resonator combination is used to provide a comb-like reflection spectrum, while in a second design a triplet-ring reflector design is used to obtain the same. A broadband silicon Bragg grating reflector is implemented on the other side of the cavity. The III-V optical amplifier is heterogeneously integrated on the 400nm thick silicon waveguide layer, which is compatible with high-performance modulator designs and allows for efficient coupling to a standard 220nm high index contrast silicon waveguide layer. In order to make the optical coupling efficient, both the III-V waveguide and the silicon waveguide are tapered, with a tip width of the III-V waveguide of around 500nm. The III-V thin film optical amplifier is implemented as a 3μm wide mesa etched through to the n-type InP contact layer. In this particular device implementation the amplifier section was 500μm long. mW-level waveguide coupled output power at 20°C and a side mode suppression ratio of more than 40dB is obtained. © 2013 SPIE.


Roelkens G.,Ghent University | Roelkens G.,Center for Nano And Biophotonics Photonics | Keyvaninia S.,Ghent University | Keyvaninia S.,Center for Nano And Biophotonics Photonics | And 26 more authors.
Asia Communications and Photonics Conference, ACP | Year: 2013

In this paper we review our work in the field of III-V/silicon photonic integrated circuits operating in the communication wavelength window. Heterogeneously integrated lasers on silicon waveguide circuits using adhesive and molecular bonding are described. © OSA 2013.


Keyvaninia S.,Ghent University | Keyvaninia S.,Center for Nano and Biophotonics Photonics | Verstuyft S.,Ghent University | Verstuyft S.,Center for Nano and Biophotonics Photonics | And 13 more authors.
Asia Communications and Photonics Conference, ACP | Year: 2012

A 4-channel multi-wavelength laser integrated on a silicon waveguide circuit is realized. Waveguide-coupled output powers of 2mW and a side mode suppression ratio of more than 45dB for all channels is realized. © OSA 2012.


Keyvaninia S.,Ghent University | Keyvaninia S.,Center for Nano and Biophotonics Photonics | Verstuyft S.,Ghent University | Verstuyft S.,Center for Nano and Biophotonics Photonics | And 18 more authors.
Optics Letters | Year: 2013

Heterogeneously integrated III-V-on-silicon second-order distributed feedback lasers utilizing an ultra-thin DVSBCB die-to-wafer bonding process are reported. A novel DFB laser design exploiting high confinement in the active waveguide is demonstrated. A 14 mW single-facet output power coupled to a silicon waveguide, 50 dB side-mode suppression ratio and continuous wave operation up to 60°C around 1550 nm is obtained. © 2013 Optical Society of America.


Beunis F.,Ghent University | Beunis F.,Center for Nano and Biophotonics Photonics | Brans T.,Ghent University | Brans T.,Center for Nano and Biophotonics Photonics | And 8 more authors.
Optical Trapping Applications, OTA 2015 | Year: 2015

Optical trapping electrophoresis is a technique that combines optical and electrical manipulation to electrically characterize single colloidal particles. With two applications we demonstrate the potential of the technique in a variety of fields. © OSA 2015.


Beunis F.,Ghent University | Beunis F.,Center for Nano and Biophotonics Photonics | Strubbe F.,Ghent University | Strubbe F.,Center for Nano and Biophotonics Photonics | And 9 more authors.
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2014

The origin of charges in nonpolar liquids with surfactant is not completely understood. This study does not only look at bulk mechanisms as the origin of charged inverse micelles, but includes processes at the liquid/electrode interfaces. We apply a voltage over a layer of nonpolar liquid with surfactant and measure the current. Information about the generation of new charges is obtained from the remaining current after the initially present charges have reached equilibrium. We find that, for low voltages, the residual current is proportional with the electric field near the electrodes. This can not be explained by bulk generation alone. We interpret these results by assuming that inverse micelles exchange charge with an adsorbed layer of surfactant molecules at the electrodes. The findings of this study are relevant for technologies such as microfluidics and electrophoretic ink, where injection of charge from the electrodes contributes to power consumption and hydrodynamic instabilities. © 2013 Elsevier B.V.


Beunis F.,Ghent University | Beunis F.,Center for Nano and Biophotonics Photonics | Strubbe F.,Ghent University | Strubbe F.,Center for Nano and Biophotonics Photonics | And 8 more authors.
Current Opinion in Colloid and Interface Science | Year: 2013

Despite the increasing importance of charges in nonpolar liquids for practical applications and fundamental research, their origin, nature and behavior are not yet completely understood. The most widely (but not generally) accepted view is that in mixtures of a nonpolar liquid with surfactant, inverse micelles act as charge carriers. A lot of research is still needed to support this view, and to gain a fundamental understanding of the electrical properties of inverse micellar solutions. In this article, we discuss transient current measurements as a valuable technique for the characterization of charged inverse micelles in nonpolar liquids, and we illustrate how they can be used to study a large number of properties, such as the concentration of both neutral and charged inverse micelles, their mobility, size, aggregation number and valency, and their behavior and generation in the bulk and at surfaces. © 2013 Elsevier Ltd.


De Koninck Y.,Ghent University | De Koninck Y.,Center for Nano and Biophotonics photonics | Roelkens G.,Ghent University | Roelkens G.,Center for Nano and Biophotonics photonics | And 2 more authors.
Laser and Photonics Reviews | Year: 2015

This article presents a novel III-V on silicon laser. This work exploits the phenomenon that a passive silicon cavity, side-coupled to a III-V waveguide, will provide high and narrow-band reflectivity into the III-V waveguide: the resonant mirror. This results in an electrically pumped laser with a threshold current of 4 mA and a side-mode suppression ratio up to 48 dB. This article presents a novel III-V on silicon laser. This work exploits the phenomenon that a passive silicon cavity, side-coupled to a III-V waveguide, will provide high and narrow-band reflectivity into the III-V waveguide: the resonant mirror. This results in an electrically pumped laser with a threshold current of 4 mA and a side-mode suppression ratio up to 48 dB. © 2015 by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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