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M.Sc. Fabian Flassig

Lehrveranstaltungen und Termine

Ausgeschriebene Angebote für Abschlussarbeiten

Probing single and multiple photons with modular superconducting nanowire detectors

Within the last years, superconducting single photon detectors (SSPDs) have proven to be one of the most versatile detectors for visible to infrared wavelengths. They outperform other single photon detectors in terms of detection efficiency (ca 90%), timing resolution (<10ps) and dark count rates (<1cps) and can be modified to detect the number of photons simultaneously hitting the detector (photon-number resolution, PNR) [1]. They can be integrated into on-chip photonic circuits, making them highly promising for future chip-based optical quantum applications.

In this project we aim at adding photon-number resolving capabilities to optical waveguide-integrated SSPDs to detect multi-photon states in optical cavities. We will use established techniques to sputter thin NbTiN and WSi superconducting films and pattern them using e-beam lithography to fabricate the superconducting detectors. These detectors will be tested and characterised at cryogenic temperatures in an optical microscopy setup to probe the fundamental detection mechanisms. We will implement a pixel-based photon number resolving technique and study the interaction of these pixels on the picosecond timescale using ultrafast lasers both in the visible as well as in the infrared regime. 


During the project, you will work in close collaboration with a team of Ph.D. students and postdocs, therefore, teamwork is crucial on this project. Some experience in the areas of optics, electronics, programming or cleanroom fabrication will be beneficial, but secondary to your personal motivation and commitment to this fascinating project. You will gain skills and knowledge and probably become an expert in various scientific research tasks, including but not limited to thin-film deposition techniques, nanoscale cleanroom fabrication and state-of-the-art electro-optical measurements at cryogenic temperatures.


[1] F. Natarajan et al. Supercond. Sci. Technol. 25 063001 (2012)

You should:

(1) Be highly motivated, (2) Be practically minded, (3) Enjoy working with state of the art optics and with control electronics / computer control and be capable of programming (e.g. Labview, C++ , Python) (4) Be willing to work as part of a small team in a dark lab in the summertime....  

You’ll get:

 (1) experience of performing sophisticated optical spectroscopy in state-of-the-art laboratories and (2) a sound understanding of the physics of superconducting thin films and quantum light detectors and, hopefully, (3) a nice paper in a journal.

geeignet als
  • Masterarbeit Physik der kondensierten Materie
  • Masterarbeit Applied and Engineering Physics
Themensteller(in): Jonathan Finley
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