La co-intégration de guides d’onde plasmonique et photonique sur une puce silicium suivant une configuration interférométrique à branche unique, dite bimodale permet d’atteindre une sensibilité inégalée lors de la détection de traces de molécules. Des puces fabriquées à bas coût et un prototype d’instrument complet démontrent leur capacité à détecter des contaminants d’intérêt pour le secteur agricole.

We demonstrate a self-referenced plasmonic augmented photonic Mach-Zehnder interferometer (MZI) for biosensing applications, incorporating a 70 mu m long aluminum plasmonic waveguide in both arms of a silicon nitride (Si3N4) MZI. Experimental results matched well with numerical simulations, showing extinction ratio (ER) values that exceed 55 dB and bulk sensitivity of 2322 nm/RIU. Wavelength stability measurements revealed 5x10-3 nm thermal dependance for an ambient temperature fluctuation of 1-degree Celsius which is 50 times better than a conventional hybrid plasmo-photonic asymmetric MZI (aMZI) configuration, highlighting the robustness of the proposed balanced sensor scheme to ambient temperature fluctuations. Moreover, the experimental results show that the proposed sensor has a limit of detection up to 2.6 x10-6 RIU. Surface sensitivity of the proposed sensing transducer was evaluated through a C-reactive protein (CRP) surface saturation measurements and found equal to 10.45 nm/RIU for protein binding. Our validated simulation model was then benchmarked against a diverse set of target bio-analytes (proteins, viruses, bacteria, fungi) with surface sensitivity values reaching up to 2306 nm/RIU, indicating the sensor's heterogeneous detection capabilities. The presented self-referencing sensor configuration offers a cost-effective yet scalable and highly sensitive approach for multiplexed on-chip detection of diverse target analytes. Published by Optica Publishing Group under the terms of the Creative Commons Attribution 4.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

In this paper, we report, for the first time to our knowledge, a new versatile and future proof diagnostic platform for diverse applications and heterogeneous biological targets. This platform relies on a plasmonic-augmented silicon photonic biochip to detect bacteria and protein biomarkers within minutes. To demonstrate the potential of this platform in diverse applications, we demonstrate the detection of two heterogeneous targets, the bacterium Escherichia coli (E. coli) and the molecule C-reactive protein (CRP) using a universal detection method. E. coli is one of the most commonly encountered bacterial pathogens involved in food monitoring, food born infections and water contamination applications, while CRP is a well-established disease severity indicator frequently used in common clinical practice. The biochip used is fully compatible with CMOS semiconductor manufacturing, while it hosts biosensors arrays for any combination of detection assays. Each biosensor exploits a 70 μm long aluminum plasmonic transducer within a silicon nitride waveguide-based Mach–Zehnder Interferometer. Each aluminum surface was silanized and biomodified with specific antibodies. Biosensing experiments revealed that CRP can be detected in diverse sample mediums, and E. coli detection was achieved in buffer at concentrations as low as 10 cells/ml within 13–25 min. The results are in good agreement with preceding numerical simulations. The modular nature of the reported biosensing platform makes it scalable and customizable, allowing nearly any combination of diagnostic tests targeting pathogens and proteins to be integrated on the same biochip for food quality monitoring, environmental monitoring, drug discovery and modern cell therapy manufacturing, or biomedical applications.

The increasing need for more efficient communication networks has been the main driving force for the development of complex photonic integration circuits combining active and passive building blocks towards advanced functionality. However, this perpetual effort comes with the cost of additive power losses and the research community has resorted to the investigation of different materials to establish efficient on-chip amplification. Among the different proposals, erbium-doped waveguide amplifiers appear to be a promising solution for high performance transmission in the C-band band with low fabrication cost, due to their CMOS compatibility and integration potential with the silicon\silicon nitride photonic platforms. In this paper we provide a holistic study for high-speed WDM transmission capabilities of a monolithically integrated Al2O3:Er3+ spiral waveguide amplifier co-integrated with Si3N4 components, providing a static characterization and a dynamic evaluation for (a) 4 × 40 Gbps, (b) 8 × 40 Gbps and (c) 8×60 Gbps WDM transmissions achieving clearly open eye diagram in all cases. The active region of the erbium doped waveguide amplifier consists of a 5.9 cm Al2O3:Er3+ spiral adiabatically coupled to passive Si3N4 waveguides combined with on chip 980 nm/1550 nm WDM Multiplexers/Demultiplexers. Experimental results reveal bit-error rate values below the KR4-FEC limit of 2×10-5 for all channels, without any DSP applied on the transmitter or receiver side for a 4×40 Gbps and 8×40 Gbps data stream transmission.

Duringthe past years, incorporating omicron ptical Circuit Switches (OCS) in high-bandwidth optical interconnects has outlined the critical challenges of achieving ultra-low fiber-to-fiber losses (FtF) and constantly decreasing costs for Photonic Integrated Circuits (PICs). This work aims to simultaneously satisfy both the low-loss and low-cost requirements by bringing two of the most successful example-technologies in the history of optics, i.e., EDFAs and ROADMs to a common Si3N4 platform. In particular, the proof-of-concept operation of a lossless four-port Silicon Photonic (SiPho) ROADM is experimentally presented for the first time based on two PIC prototypes on a Si3N4 platform, including a monolithic-integrated 5.9 cm-long spiral Al2O3:Er3+ Erbium Doped Waveguide Amplifier (EDWA) with 15 dB signal enhancement capabilities and a lattice MZI-interleaver ROAM layout with 100 GHz channel spacing. Considering an ultra-low 2.55 dB FtF loss of the ROADM along with 0.5 dB loss for each of the two coupling-interfaces between the Si3N4 and Al2O3:Er3+ waveguide layers, a cumulative loss of 3.55 dB is obtained, which can be compensated by the 3.6 dB net gain provided by the EDWA to four incoming WDM signals of -1.7 dBm/channel. Lossless wavelength-routing operation is validated at up to 240 Gb/s WDM (4 lambda x 60 Gb/s) data traffic, while the cascadability of the proposed device is benchmarked in a realistic two-stage optical bus topology with 10 km single mode fiber that selectively routes 4 lambda x 25 Gb/s WDM data channels to any of its eight Drop output ports. This work forms the first demonstration of lossless ROADM operation exclusively on SiPho technology, highlighting a promising roadmap for large scale SiPho switching matrices and more complex PICs co-integrated with EDWAs.

We report an 8×40Gb/s WDM data transmission through an Al2O3: Er3+ spiral waveguide amplifier on Si3N4 featuring 1.8dB/cm net gain. All data channels present clear eye diagrams and bit-error rate values above the KR4-FEC limit.

On chip waveguide optical amplifiers have been extensively studied over the last years, with a wide variety of materials tested and proposed for different applications. Among the most prominent solutions for on-chip amplification, erbium doped waveguide amplifiers (EDWAs) are able to offer attractive performance metrics that can exceed SOA-based amplification solutions in traditional single and multi-channel systems. In this letter, we experimentally demonstrate a record high $8\times 40$ Gbps non return to zero (NRZ) wavelength division multiplexing (WDM) data amplification through a 5.9 cm long on-chip amplifier consisting of an erbium-doped aluminum oxide spiral waveguide monolithically integrated on the Si3N4 platform. Experimental results show more than 12.7 dB amplification per channel for low saturation total input power of −2.75 dBm, and clear eye diagrams and bit-error rate values below the KR4-FEC limit of $2\times 10 ^{-5}$ for all eight channels without any digital signal processing (DSP) applied to the signal to the receiver or transmitter side. The high losses from the fiber to chip interfaces, however, prevented achieving device net gain.

The first demonstration of a lossless four-port silicon photonic ROADM-node based on a monolithic-integrated spiral Al2O3:Er3+ Erbium Doped Waveguide Amplifier and MZI-interleaver layout on a Si3N4 platform is presented, routing a 4×50Gb/s WDM data-traffic capacity.

We demonstrate a novel theoretical framework for refractive index Mach-Zehnder interferometric (MZI) sensors that can accurately calculate the sensor FSR and sensitivity while taking into account waveguide effective index dispersion and dip splitting effects. In contrast to the state-of-the-art mathematical equation that relates sensitivity with FSR, our analysis concludes to a mathematical expression that retains its validity and accuracy both in low and large FSR sensor layouts, suggesting its suitability for use in optimizing sensor performance even in the high-sensitivity, high-FSR configurations. This is validated by applying our theory to integrated plasmo-photonic MZI sensors with FSR values up to hundreds of nm, confirming our theoretical results through accurate numerical and circuit-level simulations and demonstrating how sensitivity can be boosted to >10(5) nm/RIU values exploiting dispersion engineering of the waveguides. To this end, our analytical formula that relates sensitivity with FSR and waveguide effective index dispersion can lead to reliable designs and well-matched fabricated modules when targeting high FSRs and high sensitivity MZI photonic integrated sensors.

Optical refractive-index sensors exploiting selective co-integration of plasmonics with silicon photonics has emerged as an attractive technology for biosensing applications that can unleash unprecedented performance breakthroughs that reaps the benefits of both technologies. However, towards this direction, a major challenge remains their integration using exclusively CMOS-compatible materials. In this context, herein, we demonstrate, for the first time to our knowledge, a CMOS-compatible plasmo-photonic Mach-Zehnder-interferometer (MZI) based on aluminum and Si3N4 waveguides, exhibiting record-high bulk sensitivity of 4764 nm/RIU with clear potential to scale up the bulk sensitivity values by properly engineering the design parameters of the MZI. The proposed sensor is composed of Si3N4 waveguides butt-coupled with an aluminum stripe in one branch to realize the sensing transducer. The reference arm is built by Si3N4 waveguides, incorporating a thermo-optic phase shifter followed by an MZI-based variable optical attenuation stage to maximize extinction ratio up to 38 dB, hence optimizing the overall sensing performance. The proposed sensor exhibits the highest bulk sensitivity among all plasmo-photonic counterparts, while complying with CMOS manufacturing standards, enabling volume manufacturing.

We demonstrate a CMOS compatible interferometric plasmo-photonic sensor exploiting Si 3 N 4 photonic and aluminum (Al) plasmonic stripe waveguides. Experimental evaluation revealed bulk sensitivity of 4764 nm/RIU, holding promise for ultra-sensitive and low cost sensing devices.

We experimentally demonstrate an integrated photonic non-volatile memory using GST phase change material on a fully etched Si3N4/SiO2-cladded waveguide for lower switching power and CMOS-compatibility, reporting interchangable switching from amorphous to crystalline state.

Optical refractive index (RI) sensors exploiting selective co-integration of plasmonics with silicon photonics in Lab-on-achip configurations are expected to disrupt Point-of-Care (POC) diagnostics, delivering performance and economic breakthroughs. Propagating surface-plasmon-polariton modes offer superior sensitivity due to their extreme overlap with the surrounding medium. In parallel, low-loss photonics act as the hosting platform with which the plasmonic losses can be sustained while allowing for multiplexed layouts via in-plane SPP excitation schemes. However, merging plasmonics with silicon photonics in a cost-effective manner, requires a truly CMOS-compatible manufacturing process. Herein, we demonstrate experimentally, the highest bulk-sensitivity among all the plasmo-photonic interferometric RI sensors, while taking the leap forward in the development of a CMOS-manufactured plasmo-photonic sensing platform merging Si3N4 photonics and aluminum plasmonics. The proposed structure relies on a butt-coupled interface between Si3N4 waveguides and a 70 μm long plasmonic stripe, deployed in one branch of a Mach-Zehnder Interferometer (MZI) serving as the sensing transducer that detects local changes in the refractive index. The lower MZI arm (reference arm) exploits the low-loss Si3N4 platform to deploy a MZI-based variable optical attenuator followed by a thermo-optic phase shifter to optimize the sensor performance achieving resonance extinction ratio values at the MZI output of more than 35 dB. Experimental evaluation of a gold-based sensor revealed a bulk refractive index sensitivity of 1930 nm/RIU. In addition, we experimentally demonstrate that the proposed plasmo-photonic waveguide platform can migrate from gold (Au) to Aluminum (Al), demonstrating the first step towards a fully CMOS compatible plasmo-photonic interferometric sensor.

We present a technology platform supported by a new process design kit (PDK) that integrates two types of aluminum plasmonic waveguides with Si photonics towards CMOS-compatible plasmo-photonic integrated circuits for sensing applications. More specifically, we demonstrate the fabrication of aluminum slot waveguide via e-beam lithography (EBL) on top of the Si$_{3}$N$_{4}$ waveguide and an optimized fabrication process of aluminum plasmonic stripe waveguides within a CMOS foundry using EBL. Experimental measurements revealed a propagation length of 6.2 m for the plasmonic slot waveguide in water at 1550 nm, reporting the first ever experimental demonstration of a plasmonic slot waveguide based on CMOS compatible metal materials in liquid environment. Propagation length in water for the aluminum stripe was measured equal to 66.8 m which is, to the best of our knowledge, the highest value among all single-mode Al-based plasmonic waveguides presented so far at 1550 nm. Moreover, we evince with simulation data the sensing capabilities of the proposed structures when incorporated in a Si$_{3}$N$_{4}$-based interferometric configuration, yielding bulk sensitivity values up to 80 nmRIU and 1300 nmRIU, corresponding to an accumulated phase change per unit length of 0.77 RIUm and 1.26 RIUm for the aluminum slot and aluminum stripe waveguide, respectively.

Plasmonic sensors, leveraging the profound exposure of propagating Surface-Plasmon-Polariton (SPP) modes over metal stripes to test analytes, became so far the "gold-standard" in plasmonic biosensing resulting in commercial available devices. However, a series of challenges associated with their bulky prism-based coupling configuration as well as their high optical losses need to be overcome in order to allow for miniaturized and multiplexed sensor layouts. In this context, selective co-integration of plasmonics with low-loss silicon-nitride photonics emerges as a promising solution towards addressing these challenges yet reaping the benefits from both technologies. In this work, we present an interferometric sensor based on a Mach-Zehnder device, where a "plasmo-photonic" waveguide branch is utilized to interrogate changes in the refractive index of a test analyte exploiting the accumulated phase change of the SPP mode being exposed in an aqueous solution. More specifically, the "plasmo-photonic" Mach-Zehnder sensor incorporates a gold plasmonic stripe with a length of 70 mu m and a width of 7 mu m that has been interfaced with Si3N4 waveguides by means of a butt-coupled interface. By conducting numerical simulations and considering the dispersion properties of the involved materials, we optimized the structural parameters of the sensor aiming at ultra-high bulk sensitivity in the order of micrometres per Refractive Index Unit (RIU).

We present a technology platform supported by a new process design kit (PDK) that integrates two types of aluminum plasmonic waveguides with Si$_{3}$N$_{4}$ photonics towards CMOS-compatible plasmo-photonic integrated circuits for sensing applications. More specifically, we demonstrate the fabrication of aluminum slot waveguide via e-beam lithography (EBL) on top of the Si$_{3}$N$_{4}$ waveguide and an optimized fabrication process of aluminum plasmonic stripe waveguides within a CMOS foundry using EBL. Experimental measurements revealed a propagation length of 6.2 μm for the plasmonic slot waveguide in water at 1550 nm, reporting the first ever experimental demonstration of a plasmonic slot waveguide based on CMOS compatible metal materials in liquid environment. Propagation length in water for the aluminum stripe was measured equal to 66.8 μm which is, to the best of our knowledge, the highest value among all single-mode Al-based plasmonic waveguides presented so far at 1550 nm. Moreover, we evince with simulation data the sensing capabilities of the proposed structures when incorporated in a Si$_{3}$N$_{4}$-based interferometric configuration, yielding bulk sensitivity values up to 80 nm/RIU and 1300 nm/RIU, corresponding to an accumulated phase change per unit length of 0.77 π/RIU/μm and 1.26 π/RIU/μm for the aluminum slot and aluminum stripe waveguide, respectively.

Plasmonics have been identified as an ideal platform for ultra-sensitive, label-free biosensors mainly due to the high field confinement on a metal-dielectric interface and the resulting strong light-matter interaction offered by surface plasmon resonances (SPRs) that can be entirely exposed to test analytes. Well-established SPR-based biosensors exploiting propagating SPRs yield superior specifications regarding bulk sensitivity compared to localized counterparts leading to already commercial available sensor devices. However, most of these systems require bulky prism-based configurations to couple light into the Surface Plasmon Polariton (SPP) mode impeding system miniaturization. In addition, SPR-based sensors suffer from intrinsic high propagation losses restricting the potential for multiple on-chip functionalities. In this context, co-integration of plasmonics with a low-loss photonic platform emerges as a viable solution towards highly sensitive, low-loss and small footprint optical sensors. In this work, we present an ultra-compact, interferometric plasmonic sensor co-integrated on a TiO2 photonic waveguide platform. The device consists of two access TiO2 photonic waveguides separated by a gold-based metal stripe which is located on top of an appropriately shorter TiO2 waveguide layer. Two metal/insulator interfaces are formed at the top (sensing arm) and bottom surfaces (reference arm) of the metal able to support SPP modes which upon excitation through the input photonic waveguide propagate along the two metal surfaces and interfere at the output waveguide realizing a single-arm Mach-Zehnder Interferometer. After optimization of the device in aqueous environment, we achieved sensitivity values as high as 2430 nm/RIU at near-infrared spectrum region for a 65 um long plasmonic stripe.

We demonstrate a photonic integrated Mach-Zehnder interferometric sensor, utilizing a plasmonic stripe waveguide in the sensing branch and a photonic variable optical attenuator and a phase shifter in the reference arm to optimize the interferometer operation. The plasmonic sensor is used to detect changes in the refractive index of the surrounding medium exploiting the accumulated phase change of the propagating Surface-PlasmonPolariton (SPP) mode that is fully exposed in an aqueous buffer solution. The variable optical attenuation stage is incorporated in the reference Si3N4 branch, as the means to counterbalance the optical losses introduced by the plasmonic branch and optimize interference at the sensor output. Bulk sensitivity values of 1930 nm/RIU were experimentally measured for a Mach Zehnder Interferometer (MZI) with a Free Spectral Range of 24.8 nm, along with extinction ratio of more than 35 dB, demonstrating the functional benefits of the co-integration of plasmonic and photonic waveguides. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

We demonstrate an interferometric plasmo-photonic sensor based on Si 3 N 4 photonic waveguides and gold Surface Plasmon Polariton waveguides. The proposed approach exhibits bulk sensitivity up to 1930 nm/RIU, holding promise for compact and ultra-sensitive interferometric sensing devices. © 2019 The Author(s)