Silicon photonic label free biosensors with coherent readout

Silicon photonics enables sensitive and label-free optical biosensors for the detection of chemical and biological substances. Different sensing architectures have been used to improve the limit of detection and increase the dynamic range response. Here, we show experimental limit of detection at state-of-the-art level using silicon nitride integrated Mach-Zehnder interferometers with coherent read-out. These preliminary results are concordant with theoretical results, showing that the proposed approach enables the use of simple read-out equipment using low-cost laser sources

Mode Converter and Multiplexer with a Subwavelength Phase Shifter for Extended Broadband Operation

4 pags., 3 figs., 1 tab.On-chip mode converters and multiplexers are fundamental components to scale the capacity of silicon optical interconnects by using different spatial modes of waveguides. Recently, we proposed a low loss and compact mode converter and multiplexer consisting of a subwavelength-engineered multimode interference coupler, tapered waveguides as phase shifter and a symmetric Y-junction. However, the narrow spectral response of the tapered phase shifter limited the device crosstalk performance. In this work, we demonstrate that the use of a subwavelength grating phase shifter with low phase-shift errors substantially reduces the crosstalk and expands the operational bandwidth. A complete multiplexer-demultiplexer link consisting of two devices in back-to-back configuration was fabricated in a 220-nm silicon-on-insulator platform. Experimental measurements of the complete link show insertion loss below 2 dB and crosstalk less than -17 dB over a bandwidth of 245 nm (1427 - 1672 nm).is work was supported in part by the Spanish Ministry of Science and Innovation (MICINN) under grants RTI2018- 097957-B-C33, RED2018-102768-T, TEC2015-71127-C2-1-R (FPI BES- 2016-077798) and NEOTEC-CDTI-SNEO20181232 (Alcyon Photonics S.L.); and the Community of Madrid – FEDER funds (S2018/NMT-4326). This project has received funding from the Horizon 2020 research and innovation program under Marie Sklodowska-Curie grant No. 73433

Subwavelength silicon photonics: keynote presentation

2020 Photonics North (PN), Niagara Falls, ON, Canada, 26-28 May 2020Subwavelength structures are enabling a host of high-performances devices in the silicon photonic platform. Here we review our progress in the field, with an emphasis on the auspicious anisotropic properties of these structures for applications ranging from broadband on-chip GRIN-lenses, to zero-birefringence waveguides and polarization splitters

Polarization splitter and rotator with subwavelength grating for enhanced fabrication tolerance

We propose a novel method to implement a compact and fabrication-tolerant polarization splitter and rotator (PSR) on the silicon-on-insulator platform. The PSR consists of a silicon wire waveguide coupled to a subwavelength grating (SWG) waveguide in an asymmetrical directional coupler. The SWG effect allows an additional degree of design freedom to engineer the equivalent material refractive index. This is advantageously used to effectively compensate for fabrication inaccuracies in PSRs. Our simulation results show that the PSR has a low TM-to-TE polar

Dispersion-engineered nanophotonic devices based on subwavelength metamaterial waveguides

2020 IEEE Photonics Conference (IPC), Vancouver, BC, Canada, 28 Sept.-1 Oct. 2020Subwavelength metamaterial waveguides are becoming an essential tool for the design of high-performance nanophotonic devices implemented on the silicon-on-insulator platform. Here we focus on dispersion engineering and present our latest advances in this field, including mode multiplexers/demultiplexers and passive phase shifters with ultra-broad bandwidths.This work has been funded in part by the Spanish Ministry of Science, Innovation and Universities (MICINN) under grants CDTI SNEO-20181232 (Alcyon Photonics S.L.), TEC2015-71127-C2-1-R (FPI scholarship BES-2016- 077798), TEC2016-80718-R, and RTI2018-097957-B-C33; the Spanish Ministry of Education, Culture and Sport (MECD) (FPU16/06762); and the Community of Madrid – FEDER funds (S2018/NMT-4326). This project has received funding from the Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant No. 734331

Silicon and germanium suspended waveguides for the mid-infrared

Both silicon and germanium are very interesting materials for mid-infrared applications, particularly sensing, due to their low material losses at long wavelengths. Silicon is low loss up to 8 μm, and germanium up to 15 μm [1]. To fully exploit these long wavelength transmission ranges of Si and Ge, and to build Si and Ge long wavelength photonic circuits, cladding materials need to have the same or larger transmission wavelength ranges than Si or Ge. One solution is to remove a lossy substrate and create Si and Ge suspended structures with air cladding. In the case of SOI, buried oxide can be removed by HF [2,3], and for the Ge-on-Si platform, Si substrate can be removed by TMAH. In this paper we report on the fabrication and characterization of suspended Ge waveguides at a wavelength of 3.8 μm, and on Si waveguides operating at a wavelength of 7.7 μm, both of which are the longest reported wavelengths for the two platforms.</p

Subwavelength grating metamaterial engineering: A new tool for silicon photonics

Subwavelength gratings (SWGs) are periodic structures with a pitch smaller than half the wavelength of the propagating light, so they behave as an equivalent homogeneous birefringent metamaterial. SWGs have found innumerable applications in the field of integrated optics over the past ten years, most of them implemented in the Silicon-on-Insulator platform (SOI). In this talk we will summarize some of our recent contributions in the development of SWG waveguide devices for near and mid-infrared wavelengths.</p

Enhanced sensitivity subwavelength grating waveguides for silicon photonics sensing applications

In this work we will review the enormous potential of subwavelength grating waveguides for sensing applications in the near and mid-infrared bands, demonstrating the capability to engineer the mode profile to maximize the light-matter interaction

Silicon Subwavelength Structures: Practical Metamaterials for Communications and Sensing

OSA Advanced Photonics Congress ¿ Integrated Photonics Research, Silicon and Nanophotonics, Washington, DC United States, 13–16 July 2020In this invited talk we review the latest advances in the surging field of photonic subwavelength metamaterials. These structures can provide enhanced, device-specific material properties and find widespread application in silicon photonicsWe acknowledge funding through Universidad de Málaga, Ministerio de Economía y Competitividad (TEC2016- 80718-R, CDTI SNEO-20181232, RTI2018-097957-B-C33), Ministerio de Educación, Cultura y Deporte (FPU16/06762, FPU16/03401, FPU17/00638), Proyecto I+D+i en el marco del Programa Operativo FEDER Andalucía 2014-2020 (UMA18-FEDERJA-219), Czech Science Foundation (Project 190062S), Alcyon Photonics (8.06/5.59.5045), the Community of Madrid – FEDER funds (S2018/NMT-4326), the Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant No. 73433