Single-photon detection, what is the limit?

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Objective

Developing ultrahigh efficiency, ultrahigh time resolution, and very high count-rate single-photon detectors is the main goal of this project.

Single photon detectors based on superconducting nanowires. The project will combine clean room nanofabrication with experimental work in quantum optics as well as design and realization of cryogenic amplifiers.

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Impact

The detection of light at the single photon level, the quantum limit, has been of interest to scientists for several decades, first as a conceptual challenge and more recently as a ubiquitous technology. At this point, single Quantum commercializes single photon detectors with detection efficiencies as high as 80% and time resolution as fast as 15 ps. Several applications in quantum technologies require devices operating with yet higher efficiencies, approaching unity as well as better time resolution. The goal of this project is to develop devices achieving simultaneously better time resolution and detection efficiencies and also to develop the required new measurement techniques to qualify the detectors.

So far, time resolution of SNSPD of sub-10 ps has been measured in Delft but the physical limit lies about two orders of magnitude beyond. Reaching extreme time resolutions with single photon detectors will enable a vast amount of applications ranging from fundamental quantum optics where high time resolution can make non-degenerate transitions indistinguishable to laser ranging where time resolution will result in unprecedented spatial resolution.

Another aspect of the project is the study of polarization dependence, where optimized polarization dependence would also be beneficial for the quantum optics community. New entanglement measurements exploiting the uncertainty relation will be realized where different transitions are made indistinguishable through the detection process. This will be realized using quantum dots in nanowires that have been used in our group to generate entangled states with high fidelity, we expect yet better results to be obtained with faster detectors.

In addition, polarization dependence studies will be carried out and detectors with optimized polarization dependence will be realized and implemented in optics experiments.

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Publications

• Efficient Single-Photon Detection with 7.7 ps Time Resolution for Photon-Correlation Measurements

  Iman Esmaeil Zadeh, Johannes W. N. Los, Ronan B. M. Gourgues, Jin Chang, Ali W. Elshaari, Julien Romain Zichi, Yuri J. van Staaden, Jeroen P. E. Swens, Nima Kalhor, Antonio Guardiani, Yun Meng, Kai Zou, Sergiy Dobrovolskiy, Andreas W. Fognini, Dennis R. Schaart, Dan Dalacu, Philip J. Poole, Michael E. Reimer, Xiaolong Hu, Silvania F. Pereira, Val Zwiller, and Sander N. Dorenbos, ACS Photonics 2020, 7, 7, 1780–1787 (2020)

• High performance superconducting nanowire single photon detectors operating at temperature from 4 to 7 K, Ronan Gourgues

  Ronan BM Gourgues, Johannes WN Los, Julien Zichi, Jin Chang, Nima Kalhor, Gabriele Bulgarini, Sander N Dorenbos, Val Zwiller, and Iman Esmaeil Zadeh, Optics express 27 (17), 24601-24609 (2019)

• Multimode-fiber-coupled superconducting nanowire single-photon detectors with high detection efficiency and time resolution

  Jin Chang, Iman Esmaeil Zadeh, Johannes W. N. Los, Julien Zichi, Andreas Fognini, Monique Gevers, Sander Dorenbos, Silvania F. Pereira, Paul Urbach, and Val Zwiller, Applied Optics 58 (36) (2019)

• Optimizing the stoichiometry of ultrathin NbTiN films for high-performance superconducting nanowire single-photon detectors

  Julien Zichi, Chang Chang, Stephan Steinhauer, Kristina von Fieandt, Johannes WN Los, Gijs Visser, Nima Kalhor, Thomas Lettner, Ali W Elshaari, Iman Esmaeil Zadeh, and Val Zwiller, Optics express 27 (19), 26579-26587 (2019)

• Controlled integration of selected detectors and emitters in photonic integrated circuits

  Ronan Gourgues, Iman Esmaeil Zadeh, Ali W Elshaari, Gabriele Bulgarini, Johannes WN Los, Julien Zichi, Dan Dalacu, Philip J Poole, Sander N Dorenbos, and Val Zwiller, Optics express 27 (3) (2019)

• Integration of colloidal PbS/CdS quantum dots with plasmonic antennas and superconducting detectors on a silicon nitride photonic platform

  Lukas Elsinger, Ronan Gourgues, Iman Esmaeil Zadeh, Jorick Maes, Antonio Guardiani, Gabriele Bulgarini, Silvania F. Pereira, Sander Dorenbos, Val Zwiller, Zeger Hens, and Dries Van Thourhout, Nano letters 19 (8), 5452-5458 (2019)

• Single- photon detectors combining high efficiency, high detection rates, and ultra-high timing resolution

  Iman Esmaeil Zadeh, Johannes WN Los, Ronan BM Gourgues, Violette Steinmetz, Gabriele Bulgarini, Sergiy M Dobrovolskiy, Val Zwiller, and Sander N Dorenbos, APL Photonics 2 (11) (2017)