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Quantum cascade laser integration on silicon-based waveguide circuits

Research Area: Integrated lasers and LEDs , Mid IR silicon photonics , Heterogeneous integration technology for silicon photonics , Silicon photonics for lab-on-chip spectroscopy

Main Researcher: Gunther Roelkens

Quantum cascade lasers (QCLs) have enabled the generation of mid-ir light (3 12 m) using epitaxially grown semiconductors. These lasers emit light because of transitions between energy levels inside the conduction band itself unlike traditional semiconductor lasers which emit light due to transitions between the conduction band and valence band. Integration of QCLs with silicon-based waveguide circuits allow the realization of compact hand held systems which can be used for sensing applications. However this integration varies significantly from the heterogeneous integration scheme using BCB bonding used in the telecom wavelength range as BCB absorbs heavily in mid-ir. Therefore, butt coupling of the QCL and the photonic chip has to be carried out using flip chip integration. Also since QCLs are power hungry devices, this integration scheme will provide efficient heat sinking and will thus ensure CW room temperature operation.

A schematic below shows a QCL integrated with a wavelength selective feedback circuit present on a photonic chip. This could be useful in realization of an integrated tunable QCL, which could replace the presently available EC-QCLs which use a moving grating for feedback.

Other people involved:

PhD thesises


    International Journals

  1. S. Radosavljevic, B. Kuyken, G. Roelkens, Efficient 5.2 um wavelength fiber-to-chip grating couplers for the Ge-on-Si and Ge-on-SOI mid-infrared waveguide platform, Optics Express, 25(16), p.19034 - 19043 (2017)  Download this Publication (3.5MB).
  2. A. Malik, S. Dwivedi, L. Van Landschoot, M. Muneeb, Y. Shimura, G. Lepage, J. Van Campenhout, W. Vanherle, T. Van Opstal, R. Loo, G. Roelkens, Ge-on-Si and Ge-on-SOI thermo-optic phase shifters for the mid-infrared, Optics Express, 22(23), p.28479-28488 (2014)  Download this Publication (5.3MB).
      International Conferences

    1. J.S.Penades, Y.Hu, M.Nedeljkovic, C. G. Littlejohns, A. Z. Khokhar, A. Malik, G. Roelkens, F. Y. Gardes, G. Z. Mashanovich, Angled MMI CWDM structure on Germanium on Silicon, 2015 Conference on Lasers and Electro-optics Europe & European Quantum Electronics Conference (CLEO Europe), Germany, p.paper CK-7.2 TUE (2015)  Download this Publication (3.5MB).

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