Photonics Research Group Home
Ghent University People
About People Research Publications Education Services
 IMEC
intern

 


Back to list

Dr. ir. Pieter Geiregat  (Associated Member)

This person is no longer working in this group.

Affiliation: Ghent University
Department of Information Technology (INTEC)
Address: Krijgslaan 281 - Building S3
9000 Gent
Belgium
Phone: +32-09-2644865
Fax: +32-9-264 3593
E-mail: Pieter.Geiregat@ugent.be
Research Area: Electrically pumed near-infrared laser using colloidal nanocrystals
PhD Thesis: Pieter Geiregat, Colloïdale 'Quantum Dots' voor geïntegreerde fotonica: van optische winst tot ultrasnelle modulatie, Colloidal Quantum Dots for Integrated Photonics: From Optical Gain to Ultrafast Modulation, 2/2015
Master Thesis: Pieter Geiregat, Infrared Quantum Dot LED, 5/2010
PieterGeiregat

Specific Research Topics

Current Postdoctoral Researchers

Current PhD Students

Graduated PhDs

Publications (64)

    International Journals

  1. C. Pang, Y. Deng, E. Kheradmand, N. Poonkottil, R. Petit, L. Elsinger, C. Detavernier, P. Geiregat, Z. Hens, D. Van Thourhout, Integrated PbS Colloidal Quantum Dot Photodiodes on Silicon Nitride Waveguides, ACS Photonics, p.10 pages doi:doi.org/10.1021/acsphotonics.3c00945 (2023)  Download this Publication (3.3MB).
  2. I. Tanghe, M. Samoli, I. Wagner, S. A. Cayan, A. H. Khan, K. Chen, J. Hodgkiss, I. Moreels, D. Van Thourhout, Z. Hens, P. Geiregat, Optical gain and lasing from bulk cadmium sulfide nanocrystals through bandgap renormalization, Nature Nanotechnology, doi:10.1038/s41565-023-01521-0 (2023)  Download this Publication (2MB).
  3. I. Tanghe, J. Llusar, JI, Climente, A. Barker, G. Paterno, F. Scotognella, A. Polovitsyn, AH. Khan, Z. Hens, D. Van Thourhout, P. Geiregat, I. Moreels, Role of Thermally Occupied Hole States in Room-Temperature Broadband Gain in CdSe/CdS Giant-Shell Nanocrystals, Advanced Optical Materials, p.paper 2201378 (9 pages) doi:10.1002/adom.202201378 (2022).
  4. I. Tanghe, J. Butkus, K. Chen, R. R. Tamming, S. Singh, Y. Ussembayev, K. Neyts, D. Van Thourhout, J. M. Hodgkiss, P. Geiregat, Broadband Optical Phase Modulation by Colloidal CdSe Quantum Wells, Nano Letters, 22(1), Belgium, p.58-64 doi:10.1021/acs.nanolett.1c03181 (2021)  Download this Publication (2.6MB).
  5. P. Geiregat, C. Roda, I. Tanghe, S. Singh, A. Di Giacomo, D. Lebrun, G. Grimaldi, J. Maes, D. Van Thourhout, I. Moreels, A. J. Houtepen, Z. Hens, Localization-limited exciton oscillator strength in colloidal CdSe nanoplatelets revealed by the optically induced stark effect, Light: Science & Applications, 10(112), Belgium, doi:10.1038/s41377-021-00548-z (2021)  Download this Publication (1.1MB).
  6. L. Elsinger, R. Petit, F. Van Acker, N. K. Zawacka, I. Tanghe, K. Neyts, C. Detavernier, P. Geiregat, Z. Hens, D. Van Thourhout, Waveguide-Coupled Colloidal Quantum Dot Light Emitting Diodes and Detectors on a Silicon Nitride Platform, Lasers & Photonics Reviews, 15(7), Belgium, p.n/a - n/a doi:10.1002/lpor.202000230 (2021).
  7. P. Schiettecatte, D. Poonia, I. Tanghe, S. Maiti, M. Failla, S. Kinge, Z. Hens, L. D. A. Siebbeles, P. Geiregat, Unraveling the Photophysics of Liquid-Phase Exfoliated Two-Dimensional ReS2 Nanoflakes, Journal of Physical Chemistry C, 125(38), Belgium, p.20993-21002 doi:10.1021/acs.jpcc.1c05268 (2020)  Download this Publication (2.6MB).
  8. P. Zhou, I. Tanghe, P. Schiettecatte, D. Van Thourhout, Z. Hens, P. Geiregat, Ultrafast carrier dynamics in colloidal WS2 nanosheets obtained through a hot injection synthesis, Journal of Chemical Physics, 151(164701), Belgium, p.8 doi:10.1063/1.5124898 (2019)  Download this Publication (17.1MB).
  9. A. Hossain Khan, V. Pinchetti, I. Tanghe, Z. Dang, B. Martin-Garcia, Z. Hens, D. Van Thourhout, P. Geiregat, S. Brovelli, I. Moreels, Tunable and Efficient Red to Near-Infrared Photoluminescence by Synergistic Exploitation of Core and Surface Silver Doping of CdSe Nanoplatelets, Chemistry of Materials, 31(4), Belgium, p.1450-1459 doi:10.1021/acs.chemmater.8b05334 (2019)  Download this Publication (3.2MB).
  10. A. Srinivasan, C. Porret, M. Pantouvaki, Y. Shimura, P. Geiregat, R. Loo, J. Van Campenhout, D. Van Thourhout, Carrier scattering induced linewidth broadening in in-situ P-doped Ge layers, Applied Physics Letters, 113(16), p.paper 161101 doi:10.1063/1.5040153 (2018)  Download this Publication (826KB).
  11. S. Bisschop, P. Geiregat, L. Elsinger, E. Drijvers, D. Van Thourhout, Z. Hens, E. Brainis, Fabrication and characterization of SiNx/Au cavities with colloidal nanocrystals, Optics Express, 26(5), p. 6046-6055 doi:10.1364/OE.26.006046 (2018)  Download this Publication (16.4MB).
  12. 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).
  13. P. Geiregat, A. J. Houtepen, L. K. Sagar, I. Infante, F. Zapata, V. Grigel, G. Allan, C. Delarue, D. Van Thourhout, Z. Hens, Continuous-wave infrared optical gain and amplified spontaneous emission at ultralow threshold by colloidal HgTe quantum dots, Nature Materials, 17, p.35-42 doi:10.1038/nmat5000 (2017)  Download this Publication (1.4MB).
  14. 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).
  15. 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).
  16. P. Geiregat, A.J. Houtepen, D. Van Thourhout, Z. Hens, All-Optical Wavelength Conversion by Picosecond Burst Absorption in Colloidal PbS Quantum Dots, ACS Nano, doi:10.1021/acsnano.5b06630 (2016)  Download this Publication (1.4MB).
  17. P. Geiregat, C. Delerue, Y. Justo, M. Aerts, F. Spoor, D. Van Thourhout, L. Siebbeles, G. Allan, A.J. Houtepen, Z. Hens, A phonon scattering bottleneck for carrier cooling in lead chalcogenide nanocrystals, ACS Nano, 9(1), p.778–788 doi:10.1021/nn5062723 (2015)  Download this Publication (3.1MB).
  18. P. Geiregat, A.J. Houtepen, Y. Justo, F.G. Grozema, D. Van Thourhout, Z. Hens, Coulomb Shifts upon Exciton Addition to Photoexcited PbS Colloidal Quantum Dots, The Journal of Physical Chemistry C, 118(38), p. 22284–22290 doi:10.1021/jp505530k (2014)  Download this Publication (1.1MB).
  19. A. Omari, W. Xie, P. Geiregat, D. Van Thourhout, Z. Hens, Modeling the optical properties of low-cost colloidal quantum dot functionalized strip SOI waveguides, Journal of Selected Topics in Quantum Electronics, 99, doi:10.1109/JSTQE.2014.2304180 (2013).
  20. Yolanda Justo, P. Geiregat, Karen Van Hoecke, Frank Vanhaecke, Celso de Mello Donga, Zeger Hens, Optical Properties of PbS/CdS Core/Shell Quantum Dots, Journal of Physical Chemistry C, 117(39), p.20171–20177 doi:10.1021/jp406774p (2013)  Download this Publication (1.9MB).
  21. A. Omari, P. Geiregat, D. Van Thourhout, Z. Hens, Light absorption in hybrid silicon-on-insulator/quantum dot waveguides, Optics Express, 21(20), p.23272-23285 doi:10.1364/OE.21.023272 (2013)  Download this Publication (1.4MB).
  22. P. Geiregat, Y. Justo, S. Flamee, S. Abe, Z. Hens, Giant and Broadband Absorption Enhancement in Colloidal Quantum Dot Monolayers through Dipolar Coupling, ACS Nano, 7(2), p.987–993 doi:10.1021/nn305524a (2012)  Download this Publication (1.3MB).
  23. B. De Geyter, K. Komorowska, E. Brainis, P. Emplit, P. Geiregat, A. Hassinen, Z. Hens, D. Van Thourhout, From fabrication to mode mapping in silicon nitride microdisk with embedded colloidal quantum dots, Applied Physics Letters, 101(16), p.161101~4 doi:10.1063/1.4758990 (2012)  Download this Publication (1MB).
  24. 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).
  25. 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).
      International Conferences

    1. C. Pang, Y. Deng, E. Kheradmand, L. Moreno Hagelsieb, D. Cheyns, P. Geiregat, Z. Hens, D. Van Thourhout, A colloidal-quantum-dot solution for photodetection beyond 1.6um, accepted for publication in Annual Symposium of the IEEE Photonics Society Benelux Chapter,  (to be published)  Download this Publication (286KB).
    2. C. Pang, Y. Deng, E. Kheradmand, N. Poonkottil, R. Petit, L. Elsinger, C. Detavernier, P. Geiregat, Z. Hens, D. Van Thourhout, Integrated Spectrometer Based on Arrayed Waveguide Grating and PbS Colloidal Quantum Dot Photodiode Array, Conference on Lasers and Electro-Optics, United States, (2023)  Download this Publication (450KB).
    3. C. Pang, Y. Deng, E. Kheradmand, R. Petit, L. Elsinger, C. Detavernier, P. Geiregat, Z. Hens, D. Van Thourhout, Monolithic heterogeneous integration of PbS colloidal quantum dot photodiode on silicon nitride, Frontiers in Optics, (2022)  Download this Publication (756KB).
    4. 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).
    5. 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).
    6. L. Elsinger, I. Tanghe, F. Van Acker, N. K. Zawacka, R. Petit, K. Neyts, C. Detavernier, P. Geiregat, Z. Hens, D. Van Thourhout, A Waveguide-Coupled Colloidal Quantum Dot LED on a Silicon Nitride Platform, Conference on Lasers and Electro-Optics, United States, p.STh1J.8 doi:10.1364/CLEO_SI.2020.STh1J.8 (2020).
    7. A. Srinivasan, C. Porret, E. Vissers, P. Geiregat, D. Van Thourhout, R. Loo, M. Pantouvaki, J. Van Campenhout, High-contrast quantum-confined Stark effect in Ge/SiGe quantum well stacks on Si with ultra-thin buffer layers, Conference on Lasers and Electro-Optics Pacific Rim, China, p.Th3C.1 doi:10.1364/CLEOPR.2018.Th3C.1 (2018).
    8. 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).
    9. Y. Zhu, W. Xie, P. Geiregat, S. Bisschop, T. Aubert, E. Brainis, Z. Hens, D. Van Thourhout, On-chip Low-threshold Silicon Nitride Distributed Feedback Colloidal Quantum Dot Laser, CLEO 2017, United States, p.paper JW2A.126  doi:10.1364/cleo_at.2017.jw2a.126 (2017)  Download this Publication (180KB).
    10. S. Bisschop, P. Geiregat, Y. Zhu, W. Xie, T. Aubert, E. Brainis, D. Van Thourhout, Z. Hens, Optical Gain with Colloidal Quantum Dots: From material photo-physics to integrated devices, Proceedings Symposium IEEE Photonics Society Benelux, Belgium, (2016)  Download this Publication (261KB).
    11. S. Bisschop, P. Geiregat, Z. Hens, D. Van Thourhout, E. Brainis, Fabrication and characterization of SiNx/Au nanopatch cavities with colloidal nanocrystals, CLEO 2016, United States, p.FTu4B.6 doi:10.1364/cleo_qels.2016.ftu4b.6 (2016)  Download this Publication (204KB).
    12. M. Kolarczik, B. Herzog, C. Ulbrich, Y. Kaptan, U. Woggon, N. Owschimikow, A. Singh, X. Li, Y. Zhu, D. Van Thourhout, P. Geiregat, Z. Hens, Biexciton-mediated modulation response of colloidal quantum dots deposited on a silicon nitride waveguide at high laser excitation rate, CLEO, United States, doi:10.1364/cleo_at.2016.jtu5a.44 (2016)  Download this Publication (373KB).
    13. Y. Zhu, W. Xie, P. Geiregat, S. Bisschop, T. Aubert, E. Brainis, Z. Hens, D. Van Thourhout, Hybrid Colloidal Quantum Dot Silicon Nitride Waveguide Gain Measurement Based on Variable Stripe Length Method, CLEO 2016, United States, doi:10.1364/cleo_at.2016.ath1j.5 (2016)  Download this Publication (273KB).
    14. S. Bisschop, J. Ciers, A. Guille, P. Geiregat, E. Brainis, Z. Hens, D. Van Thourhout, Subwavelength Nanopatch SiN/Au Nanocavities with Colloidal Nanocrystals, European Conference on Lasers and Electro-Optics - European Quantum Electronics Conference, Germany, (2015).
    15. P. Geiregat, A. Houtepen, D. Van Thourhout, Z. Hens, Low Power All-­‐Optical Wavelength Conversion with Terahertz Refresh Rates using Colloidal Nanocrystals, CLEO Europe, Germany, p.paper EG-P.13 MON (2015).
    16. P. Geiregat, A.J. Houtepen, F. Grozema, D. Van Thourhout, Z. Hens, Picosecond All-Optical Wavelength Conversion using Hot Carrier Intraband Absorption in Colloidal Nanocrystals, E-MRS Spring Meeting, France, (2015)  Download this Publication (892KB).
    17. P. Geiregat, C. Delerue, Y. Justo, M. Aerts, F. Spoor, D. Van Thourhout, L. D. Siebbeles, G. Allan, A.J. Houtepen, Z. Hens, A Phonon Scattering Bottleneck for Carrier Cooling in Lead-Chalcogenide Nanocrystals, E-MRS Spring Meeting, France, doi:10.1557/opl.2015.595 (2015)  Download this Publication (892KB).
    18. P. Geiregat, A.J. Houtepen, F.C. Grozema, D. Van Thourhout, Z. Hens, Picosecond All-Optical Wavelength Conversion using Hot Carrier Intraband Absorption in Colloidal PbS Nanocrystals , MRS Spring Meeting - WW4.04, United States, (2015).
    19. P. Geiregat, A.J. Houtepen, D. Van Thourhout, C. Delerue, Z. Hens, Properties and Dynamics of Cooling Charge Carriers in Lead Sulfide Quantum Dots, International Conference on Fundamental Processes in Semiconductor Nanocrystals, United Kingdom, (2014).
    20. P. Geiregat, A. Houtepen, L.K. Sagar, C. Delerue, G. Allan, D. Van Thourhout, Z. Hens, Thresholdless Optical Gain using Colloidal HgTe Nanocrystals, CLEO, United States, p.paper FtH4C4 doi:10.1364/cleo_qels.2014.fth4c.4 (2014)  Download this Publication (214KB).
    21. P. Geiregat, A. Houtepen, C. Delerue, G. Allan, L.K. Sagar, D. Van Thourhout, Z. Hens, Near-Thresholdless Optical Gain using Colloidal HgTe Nanocrystals, 30 Years of Colloidal Quantum Dots, (2014).
    22. P. Geiregat, A. Houtepen, M. Aerts, D. Van Thourhout, C. Delerue, Z. Hens, Properties and dynamics of cooling charge carriers in lead sulfide quantum dots, Nanax 2014 , Austria, (2014).
    23. P. Geiregat, Arjan Houtepen, Michiel Aerts, Christophe Delerue, D. Van Thourhout, Zeger Hens, Hyperspectral Analysis of Ultrafast Hot Carrier Dynamics in Pb-chalcogenide Nanocrystals: a Case for Slow Cooling, International Quantum Dot Meeting 2014, Italy, (2013)  Download this Publication (90KB).
    24. Z. Hens, A. Omari, P. Geiregat, D. Van Thourhout, Optical Properties of SOI Waveguides Functionalized with Close-Packed Quantum Dot Films, 15th International Conference on Transparent Optical Networks (ICTON 2013), Spain, p.paper We.D6.2 doi:10.1109/icton.2013.6603021 (2013)  Download this Publication (1.7MB).
    25. P. Geiregat, A. Omari, Yolanda Justo, D. Van Thourhout, Zeger Hens, Absorption Enhancement in 2D Nanocrystal Superlattices through Near-Field Dipolar Coupling: A Novel Optical Phenomenon at the Nanoscale, Laser Science to Photonics Applications (CLEO 2013), United States, p.paper QTu1A.7 doi:10.1364/CLEO_QELS.2013.QTu1A.7 (2013)  Download this Publication (147KB).
    26. A. Omari, P. Geiregat, D. Van Thourhout, Z. Hens, Assessing colloidal quantum dot optical properties through free standing layers on photonic waveguides, EMRS 2013 Spring & Bilateral, (2013).
    27. A. Omari, P. Geiregat, D. Van Thourhout, Z. Hens, Modelling colloidal quantum dots on SOI photonic waveguides, EMRS 2013 Spring & Bilateral, (2013).
    28. A. Omari, P. Geiregat, D. Van Thourhout, Z. Hens, Probing the optical constants at the nanoscale of colloidal prepared films through optical waveguides., NWO Scientific meeting on Chemistry related to Physics & Material Sciences, Netherlands, (2013).
    29. P. Geiregat, Y. Justo, S. Abe, S. Flamee, Z. Hens, Giant and Broadband Absorption Enhancement in Colloidal Nanocrystal Superlattices through Dipolar Coupling, EMRS Spring Meeting, France, (2013).
    30. B. De Geyter, P. Geiregat, K. Komorowska, A. Hassinen, E. Brainis, D. Van Thourhout, Z. Hens, Embedding Colloidal Nanocrystals in Silicon Nitride Micro-Disk Resonators: From mode-mapping to single dot spectroscopy, EMRS Spring Meeting, France, (2013).
    31. A. Omari, H. Shinchi, P. Geiregat, D. Van Thourhout, Z. Hens, Characterisation of PbS/CdS Qdot absorption on SOI waveguides, Poceedings Symposium IEEE Photonics Society Benelux Chapter, 2012, Mons , Belgium, p.295-298 (2012)  Download this Publication (463KB).
    32. B. De Geyter, P. Geiregat, Y. Gao, S. ten Cate, A.J. Houtepen, J. M. Schins, D. Van Thourhout, L. D.A. Siebbeles, Z. Hens, Broadband and picosecond intraband absorption in lead based colloidal quantum dots, 14th International Conference on Transparant Optical Networks (ICTON 2012) (invited), United Kingdom, p.paper Th.A5.4 doi:10.1109/icton.2012.6254469 (2012)  Download this Publication (372KB).
    33. Kilian Devloo-Casier, Jolien Dendooven, Karl F. Ludwig, P. Geiregat, Zeger Hens, Cristophe Detavernier, Nanoscale area selective ZnO growth between a monolayer of nanocrystals, International Conference on Atomic Layer Depsosition, Germany, (2012)  Download this Publication (1.7MB).
    34. P. Geiregat, B. De Geyter, S. Carillo, A. Houtepen, Y. Gao, S. Ten Cate, J. Schins, D. Van Thourhout, C. Delerue, L. Siebbeles, Z. Hens, Broadband and Picosecond Intraband Relaxation in Lead Chalcogenide Nanocrystals, International Quantum Dot Conference 2012, (2012).
    35. P. Geiregat, Y. Justo, H. Zeger, Giant Absorption Enhancement in Colloidal Quantum Dot Supercrystals, International Quantum Dot Conference 2012, United States, (2012)  Download this Publication (266KB).
    36. B. De Geyter, P. Geiregat, A. J. Houtepen, D. Van Thourhout, L. Siebbeles, Z. Hens, Ultrafast Photoinduced Intraband Absorption in PbS, PbSe and PbSe/CdSe Core/Shell Nanocrystals for near-Infrared to Mid-Infrared All-Optical Signal Processing, MRS Fall Meeting 2011, United States, (2011)  Download this Publication (233KB).
    37. Q. Lu, P. Geiregat, D. Van Thourhout, Zeger Hens, Design of Nanocrystal Light Source for Silicon Photonics, IEEE Photonics Annual Meeting 2011, WP4, United States, p.527-528 (2011)  Download this Publication (220KB).
        National Conferences

      1. K.Devloo-Casier, J. Dendooven, Karl F. Ludwig, P. Geiregat, Z. Hens, C. Detavernier, Nanoscale area selective ZnO growth between a monolayer of nanocrystals, PhD Symposium Faculty of Science (UGent), Belgium, (2014).
      2. P. Geiregat, Yolanda Justo, Zeger Hens, Giant Absorption Enhancement in Colloidal Quantum Dot Supercrystals, NB Photonics Annual Meeting, Belgium, (2011).
      Click here for a printable publication list.

      Back to list