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The collection of single‐photon emission from a quantum dot (QD) in a Bragg waveguide through a photonic wire bond (PWB) via free‐space resonant frequency pumping at 1.6 K is demonstrated. The in‐fiber single photons show a small multiphoton contribution, quantified by a low second order photon autocorrelation value of gcorr(2)(0)=(5.9±0.8)×10−3$g_{{\mathrm{corr}}}^{(2)}\;(0) = ({5.9 \pm 0.8})\; \times {10^{ - 3}}$ (background‐corrected) or graw(2)(0)=(9.5±1.4)×10−2$g_{{\mathrm{raw}}}^{(2)}(0)\; = ({9.5 \pm 1.4})\; \times {10^{ - 2}}{\mathrm{\;}}$(raw data). The decay time of the QD is measured to be τ=440${\mathrm{\tau \;}} = {\mathrm{\;}}440$ ps. The PWB obviates the need for in‐cryostat alignment of the single‐photon source with an optical fiber and thus offers a route to scalable integration of quantum photonic devices in a cryogenic environment. Uniquely, the approach combines the QD‐waveguide technique, enabling resonant driving of individual QDs without the need for cross‐polarization filtering, and the PWB for deterministic, alignment‐free coupling of single‐photon sources to optical fibers. [ABSTRACT FROM AUTHOR]

In the present work, a method to determine the optical waveguide properties of silicon‐on‐insulator (SOI) integrated circuits has been developed. According to the explicit relations between transfer functions of a microring resonator and the waveguide properties the inner optical parameters could be extracted. An increase in accuracy can be achieved by measuring the transfer functions of additional elements, such as a straight waveguide and a directional coupler. It is shown that the developed method allows one to determine the coupling coefficient, damping decrement, Bragg grating coupler efficiency, and waveguide dispersion with high accuracy. The obtained optical waveguide properties are used for modeling the transmission of a Mach–Zehnder interferometer which is used as a control element. The modeling results demonstrate a good agreement with the experimental characteristics. The developed method paves the way to local characterization of large‐scale SOI integrated circuits by using the aforementioned structures as reference elements. [ABSTRACT FROM AUTHOR]

Abstract: Silicon Photonics technology is rapidly maturing as a platform for larger‐scale photonic circuits. As a result, the associated design methodologies are also evolving from component‐oriented design to a more circuit‐oriented design flow, that makes abstraction from the very detailed geometry and enables design on a larger scale. In this paper, the state of this emerging photonic circuit design flow and its synergies with electronic design automation (EDA) are reviewed. The design flow from schematic capture, circuit simulation, layout and verification is covered. The similarities and the differences between photonic and electronic design, and the challenges and opportunities that present themselves in the new photonic design landscape, such as variability analysis, photonic‐electronic co‐simulation and compact model definition are discussed. [ABSTRACT FROM AUTHOR]

Selective optical filters with high rejection levels are of fundamental importance for a wide range of advanced photonic circuits. However, the implementation of high‐rejection on‐chip optical filters is seriously hampered by phase errors arising from fabrication imperfections. Due to coherent interactions, unwanted phase‐shifts result in detrimental destructive interferences that distort the filter response, whatever the chosen strategy (resonators, interferometers, Bragg filters, etc.). State‐of‐the‐art high‐rejection filters partially circumvent the sensitivity to phase errors by means of active tuning, complicating device fabrication and operation. Here, a new approach based on coherency‐broken Bragg filters is proposed to overcome this fundamental limitation. Non‐coherent interaction among modal‐engineered waveguide Bragg gratings separated by single‐mode waveguides is exploited to yield effective cascading, even in the presence of phase errors. This technologically independent approach allows seamless combination of filter stages with moderate performance free of active control, providing a dramatic increase of on‐chip rejection. Based on this concept, on‐chip non‐coherent cascading of Si Bragg filters is experimentally demonstrated, achieving a light rejection exceeding 80 dB, the largest value reported for an all‐passive silicon filter. [ABSTRACT FROM AUTHOR]