Photonics Research Group Home
Ghent University Research Topics
About People Research Publications Education Services


Silicon compatible laser based on colloidal quantum dots

Research Area: Heterogeneous integration technology for silicon photonics , Integrated lasers and LEDs

Main Researcher: Pieter Geiregat

A cheap, reliable and robust light source integrated on silicon is often identified as a major missing link in silicon photonics research. We are using a different approach than usual by depositing colloidal quantum dots, produced in suspension through wet chemical synthesis. These quantum dots have a very efficient photoluminescence and can be tuned to a specific emission wavelength by controlling their size.

TEM image of a colloidal PbSe nanocrystal
TEM image of a colloidal PbSe nanocrystal

The synthesis of these IV-VI nanocrystals (PbSe, PbS, PbTe) has been perfected at the Physics and Chemistry of Nanostructures Group. Further development of core/shell nanocrystals is ongoing, coating the PbX quantum dots with the higher bandgap CdX (X=Se,S,Te). This stabilizes the luminescence and resolves oxidation problems. Furthermore engineering is being done to develop a core/shell quantum dot with staggered or type-II band alignment. These have very promising properties like ultra-low threshold for lasing applications.

Other people involved:

Related Research Projects

PhD thesises


    International Journals

  1. Y. Zhu, J. Wang, W. Xie, B. Tian, Y. Li, E. Brainis, Yuqing Jiao, D. Van Thourhout, Ultra-Compact Silicon Nitride Grating Coupler for Microscopy Systems, Optics Express, 25(26), p.33297-33304 doi:10.1364/oe.25.033297 (2017)  Download this Publication (2.4MB).
  2. M. Kolarczik, C. Ulbrich, P. Geiregat, Y. Zhu, L. Kishore Sagar, A.Singh, B.Herzog, A.W. Achtstein, X. Li, D. Van Thourhout, Z. Hens, N. Owschimikow, U. Woggon, Sideband pump-probe technique resolves nonlinear modulation response of PbS/CdS quantum dots on a silicon nitride waveguide, APL Photonics, 3(1), p.016101 (10 pages) doi:10.1063/1.5005490 (2017)  Download this Publication (3.5MB).
  3. Y. Zhu, W. Xie, S. Bisschop, T. Aubert, E. Brainis, P. Geiregat, Z. Hens, D. Van Thourhout, On-Chip SIngle-Mode Distributed Feedback Colloidal Quantum Dot Laser under Nanosecond Pumping, ACS Photonics, United States, p.2446-2452 doi:10.1021/acsphotonics.7b00644 (2017)  Download this Publication (2.2MB).
  4. W. Xie, T.Stoferle, G.Raino, T.Aubert, S. Bisschop, Y. Zhu, R.F. Mahrt, P. Geiregat, E. Brainis, Z. Hens, D. Van Thourhout, On-Chip Integrated Quantum-Dot-Silicon-Nitride Microdisk Lasers, Advanced Materials, 29, p.1604866 (6 pages) doi:10.1002/adma.201604866 (2017)  Download this Publication (690KB).
  5. W. Xie, Y. Zhu, T. Aubert, Z. Hens, E. Brainis, D. Van Thourhout, Fabrication and characterization of on-chip silicon nitride microdisk integrated with colloidal quantum dots, Optics Express, 24(2), United States, p.A114-A122 doi:10.1364/OE.24.00A114 (2015)  Download this Publication (1.6MB).
  6. W. Xie, R. Gomes, T. Aubert, S. Bisschop, Y. Zhu, Z. Hens, E. Brainis, D. Van Thourhout, Nanoscale and Single-Dot Patterning of Colloidal Quantum Dots, Nano Lett., 15(11), United States, p.7481–7487 doi:10.1021/acs.nanolett.5b03068 (2015)  Download this Publication (3.8MB).
  7. A. Subramanian, E.M.P. Ryckeboer, A. Dhakal, F. Peyskens, A. Malik, B. Kuyken, H. Zhao, S. Pathak, A. Ruocco, A. De Groote, P.C. Wuytens, D. Martens, F. Leo, W. Xie, U.D. Dave, M. Muneeb, Pol Van Dorpe, J. Van Campenhout, W. Bogaerts, P. Bienstman, N. Le Thomas, D. Van Thourhout, Zeger Hens, G. Roelkens, R. Baets, Silicon and silicon nitride photonic circuits for spectroscopic sensing on-a-chip , Photonics Research (invited), 5(3), p.B47 doi:10.1364/PRJ.3.000B47 (2015)  Download this Publication (1.5MB).
  8. W. Xie, Y. Zhu, Tangi Aubert, S. Verstuyft, Zeger Hens, D. Van Thourhout, Low-Loss Silicon Nitride Waveguide Hybridly Integrated With Colloidal Quantum Dots, Optics Express, 23(9), United States, p.12152-12160 doi:10.1364/OE.23.012152 (2015)  Download this Publication (2.9MB).
  9. B. De Geyter, Houtepen, Arjan J., Carrillo, Sergio, P. Geiregat, Gao, Yunan, Ten Cate, Sybren, Schins, Juleon M., D. Van Thourhout, Delerue, Cristophe, Siebbeles, Laurens D.A., Hens, Zeger, Broadband and Picosecond Intraband Relaxation in Lead-Based Colloidal Quantum Dots, ACS Nano, 6(7), p.6067–6074 doi:10.1021/nn301149x (2012)  Download this Publication (1022KB).
  10. Yolanda Justo, Bart Goris, John Sundar Kamal, P. Geiregat, Sara Bals, Zeger Hens, Multipe Dot-in-Rod PbS/CdS Heterostructures with High Photoluminescence Quantum Yield in the Near-Infrared, Journal of the American Chemical Society, 134(12), p.5484–5487 doi:10.1021/ja300337d (2012)  Download this Publication (282KB).
  11. I. Moreels, B. De Geyter, D. Van Thourhout, Z. Hens, Transmission of a quantum-dot-silicon-on-insulator hybrid notch filter, Journal of the Optical Society of America B-Optical Physics, 26(6), p.1243-1247 doi:10.1364/josab.26.001243 (2009)  Download this Publication (530KB).
  12. K. Lambert, B. De Geyter, I. Moreels, Z. Hens, PbTe|CdTe core|shell particles by cation exchange, a HR-TEM study, Chemistry of Materials, 21(5), p.778-780 doi:10.1021/cm8029399 (2009)  Download this Publication (185KB).
      International Conferences

    1. K. Molkens, I. Tanghe, Dhruv Saxena, Wai Kit Ng, Riccardo Sapienza, P. Geiregat, D. Van Thourhout, Coupled Micro Ring Lasers based on Hybrid Integration of Colloidal Quantum Dots, Conference on Lasers and Electro-Optics, United States, (2022)  Download this Publication (898KB).
    2. K. Molkens, I. Tanghe, Dhruv Saxena, Wai Kit Ng, Riccardo Sapienza, P. Geiregat, D. Van Thourhout, Localized and extended states in colloidal quantum dots-based microring lasers., EMRS fall meeting, (2021)  Download this Publication (4MB).
    3. L. Elsinger, Y. Zhu, W. Xie, I. Tanghe, S. Bisschop, V. Chandrasekaran, E. Brainis, P. Geiregat, Z. Hens, D. Van Thourhout, A Hybrid SiN-QDOT platform for visible photonics, CLEO 2018 (invited), United States, p.SW4I.4 doi:10.1364/cleo_si.2018.sw4i.4 (2018)  Download this Publication (258KB).
    4. W. Xie, T. Stoferle, G. Raino, T. Aubert, Y. Zhu, R.F. Mahrt, E. Brainis, Z. Hens, D. Van Thourhout, Integrated Silicon Nitride Microdisk Lasers Based on Quantum Dots, CLEO 2016, United States, p.paper JTh4B.6 doi:10.1364/CLEO_AT.2016.JTh4B.6 (2016)  Download this Publication (392KB).
    5. W. Xie, Y. Zhu, T. Aubert, Z. Hens, E. Brainis, D. Van Thourhout, Integration of silicon nitride photonics with nanoscale materials: from passive to active photonics ICs, The International Symposium on Optoelectronic Technology and Application (invited), China, (2016)  Download this Publication (239KB).
    6. W. Xie, Y. Zhu, T. Aubert, Z. Hens, E. Brainis, D. Van Thourhout, On-chip Hybrid Integration of Silicon Nitride Microdisk With Colloidal Quantum Dots, 12th International Conference on Group IV Photonics, ThB2, Canada, p.159-160 doi:10.1109/group4.2015.7305912 (2015)  Download this Publication (412KB).
    7. W. Xie, D. Van Thourhout, Fabrication of high-Q silicon nitride microdisk resonator coupled with on-chip waveguide, Proceedings of the 19th Annual Symposium of the IEEE Photonics Society Benelux Chapter, Netherlands, p.145-148 (2014)  Download this Publication (1.6MB).
    8. S. Bisschop, Y. Zhu, W. Xie, Antoine Guille, Zeger Hens, D. Van Thourhout, E. Brainis, Progress Towards On-chip Single Photon Sources Based on Colloidal Quantum Dots in Silicon Nitride Devices, CLEO, United States, doi:10.1364/cleo_at.2014.jw2a.127 (2014)  Download this Publication (241KB).
    9. W. Xie, D. Van Thourhout, High-Q Free-standing Silicon Nitride Microdisk Vertically Coupled with On-chip Waveguide, CLEO 2014, United States, doi:10.1364/CLEO_SI.2014.STu3M.3 (2014)  Download this Publication (320KB).
    10. Y. Zhu, W. Xie, S. Verstuyft, Tangi Aubert, Zeger Hens, D. Van Thourhout, Colloidal quantum dot silicon nitride platform, Proceedings of the 2013 Annual Symposium of the IEEE Photonics Society Belenux Chapter, Netherlands, p.175-178 (2013)  Download this Publication (193KB).
    11. W. Xie, M. Fiers, S. Selvaraja, J. Van Campenhout, P. Absil, D. Van Thourhout, High-Q photonic crystal nanocavities on 300 mm SOI substrate fabricated by 193 nm immersion lithography, Proceedings of the 2012 Annual Symposium of the IEEE Photonics Society Benelux Chapter, Belgium, p.183-186 (2012)  Download this Publication (439KB).

        Back to overview