Passive components of silicon photonics

Together with IMS Chips, INT developed an extensive library of passive components for complex optical systems using INT/IMS technology. In addition to grating couplers and waveguides, these include multimode interferometers, 90° hybrids, and arrayed waveguide gratings.

The INT works very closely with the IMS Chips in both technology development and the development of components for silicon photonics. This has resulted in an extensive library of passive components for complex optical systems, some of which are listed below.

Waveguide

The basis for the development of complex systems are the connecting elements of the individual circuit components. This requires low-loss waveguides, which must be adapted in their dimensions depending on the requirements. Low-loss single-mode waveguides can be realized in this technology for both polarizations. In addition to ridge and rib waveguides, sub-wavelength waveguides are also being investigated at INT.

Cross-section of a ribbed waveguide on oxide (left) and top view of a subwavelength waveguide (right).
Cross-section of a ribbed waveguide on oxide (left) and top view of a subwavelength waveguide (right).
Image: IMS Chips
Simulated self-image of the input signal for dimensioning an MMI.
Simulated self-image of the input signal for dimensioning an MMI.

Multimode interferometer

Multimode interferometers are used, for example, as optical signal splitters or to determine the mutual phase relationship of two optical signals in an interferometer. Many optical modes are excited in a wide bridge via single-mode waveguide inputs. These modes propagate and superimpose themselves after certain distances to form so-called self-images. The couplers can be dimensioned so that the self-images of several inputs fall on the same number of outputs and the input signals superimpose themselves with defined phase differences.

90° hybrid

A 90° hybrid coupler was designed based on a multimode interference coupler. Subwavelength structuring of the sides reduced the phase error at the outputs.

Test structure for characterizing a 90° hybrid and recording the lateral subwavelength grating.
Test structure for characterizing a 90° hybrid and recording the lateral subwavelength grating.
Image: INT (left), IMS-Chips (right)
Chip photo of an AWG
Chip photo of an AWG

Arrayed-waveguide gratings

The use of a large number of optical channels significantly increases the total capacity of a single fiber. Arrayed waveguide gratings (AWGs) can be used to split or combine signals spectrally, making them key components in transmission systems that use wavelength division multiplexing.

Publications

  1. 2024

    1. S. Abdani, R. T. Ako, M. Bhaskaran, and S. Sriram, “Deep learning enhanced optimization of a broadband and wide-angle reflective linear terahertz polarization converter,” in Metamaterials, Metadevices, and Metasystems 2024, 2024, p. 42.
    2. S. Abdani, C. Schweikert, W. Vogel, and G. Rademacher, “Compact Symmetric 2x2 Inverse-Designed Power Splitter for Integrated Photonics,” in International Conference on Numerical Simulation of Optoelectronic Devices (NUSOD), 2024, p. MP19, pp. 1–2.

  2. 2022

    1. C. Schweikert, A. Tsianaka, N. Hoppe, R. H. Klenk, R. Elster, M. Greul, M. Kaschel, A. Southan, W. Vogel, and M. Berroth, “Integrated polarization mode interferometer in 220 nm silicon-on-insulator technology,” Optics Letters, vol. 47, pp. 4536–4539, 2022.

  3. 2021

    1. N. Hoppe, C. Schweikert, W. Vogel, R. Elster, P. Adam, and M. Berroth, “Enhanced Generalized Mach-Zehnder Interferometer for Tunable Channel Routing,” in IEEE Summer Topicals Meeting Series (SUM), 2021, p. WB2.
    2. M. Leyzner, N. Hoppe, C. Schweikert, W. Vogel, and M. Berroth, “On-Chip Polarization Rotator in 250 nm Silicon-on-Insulator Technology,” in VDE/ITG Fachtagung Photonische Netze, 2021.

  4. 2018

    1. N. Hoppe, W. Vogel, L. Rathgeber, T. Föhn, M. Félix Rosa, M. Kaschel, and M. Berroth, “Low-loss Silicon Photonics Platform for Optical Mode Engineering,” in European Conference on Integrated Optics (ECIO), Valencia, Spain, 2018, p. pp. 203–205.

  5. 2014

    1. T. Föhn, N. Hoppe, W. Vogel, M. Schmidt, M. Félix Rosa, M. Berroth, J. Butschke, and F. Letzkus, “3D-simulation and characterization of subwavelength grating waveguides in SOI,” in International Conference on Numerical Simulation of Optoelectronic Devices (NUSOD), Palma de Mallorca, 2014, pp. 137–138.
    2. T. Föhn, W. Vogel, M. Schmidt, M. Berroth, J. Butschke, and F. Letzkus, “Optimized 90° Hybrids with Sidewall Grating in Silicon on Insulator,” in Optical Fiber Communication Conference (OFC), San Francisco, California, 2014, p. Th3F.

Contact

This image shows Wolfgang Vogel

Wolfgang Vogel

Dr.-Ing.

Senior Lecturer / Vice Director

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