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projects

The vision of the FWF-funded Cluster of Excellence Quantum Science Austria is to become the premier place in the world, in which to do research in fundamental quantum physics. We will achieve this through cooperation between all the quantum researchers working in Austria in the field of fundamental quantum physics. (read more ...)

The aim of the FFG/Quantum Austria project HuSQI is the coordinated acquisition and installation of closed-cycle cryogenic stations equipped with advanced electronic and optical equipment for the rapid characterization and uninterrupted operation of photonic and superconducting solid-state devices for forefront research in quantum science and new applications in quantum computation and communication.

In our research subgroup on Quantum Dots we work with GaAs/AlGaAs or InP/InAsP quantum dots, towards three main projects: (1) developing robust excitation schemes to generate single or entangled photon pairs  (2) generating time-bin entangled photons (3) designing and fabricating photonic cavity structures for improved photon extraction efficiency (read more...)

In our project IGUANA on Integrated Quantum Rangefinding we utilize the photon pairs produced in our Bragg-reflection waveguides for a quantum protocol for remote sensing. Inspired by quantum illumination it hinges on the thermal photon-pair probability distribution generated by parametric down-conversion. Different from quantum illumination, the protocol does not offer an improved signal-to-noise ratio, but perfect covertness guaranteed by the laws of quantum mechanics. (read more...)

In our project UNIQORN on Affordable Quantum Communication for Everyone we exploit the high effective optical nonlinearity of our AlGaAs waveguides and the low-loss polymer structures of our collaborators at the HHI in Berlin in a hybrid approach. Our Bragg-reflection waveguides act as a source of photon pairs at the telecom wavelength range, which are subsequently time-bin entangled in on-chip polymer michelson interferometers. (read more...)

 

In the D-A-CH project On-chip microlaser driven sources of indistinguishable photons for quantum networks we aim to combine the advantages of semiconductor quantum dots and Bragg-reflection waveguides in a single device. By exploiting the high optical nonlinearity of AlGaAs BRWs, we convert the single photons generated by an embedded quantum dot to telecom wavelengths via difference frequency generation. (read more...)

Starting from a triple-slit experiment we are investigating higher-order, i.e. genuine Multi-Path Interferences for possible deviations from quantum mechanics as well as the possibility to represent quantum mechanics by hypercomplex (e.g. quaternion) numbers instead of complex ones. For this purpose we have a five-path interferometer and measure the ration of higher-order to regular interference. (read more...)

Our project on many-particle interference takes a look at interference phenomena beyond single particles or waves. For multiple identical particles, another layer of interference arises due to their exchange symmetry. We investigate conditions for fully destructive interference theoretically as well as experimentally via multi-photon states from nonlinear crystals or quantum dots. (read more...)

Our SFB project P14 - Integrated Quantum Photonics targets optical quantum information processing on a highly integrated III-V semiconductor platform. This platform is extremely versatile, because it goes beyond just passive elements but hosts single photon and photon pair sources based on quantum dots and on spontaneous parametric down-conversion. (read more...)

 

Concluded projects can be found HERE

collaborations

Buchleitner Andreas, University of Freiburg, Germany

Höfling Sven & Tobias Huber, University of Wuerzburg, Germany

Nolte Stefan, Institute of Applied Physics, Jena, Germany

Heindel Tobias, Technical University of Berlin, Germany

Walther Philipp, University of Vienna, Austria

Hall Kimberley, Dalhousie University, Canada

Dalacu Dan, National Research Council, Canada

Imamoglu Atac, ETH Zuerich, Switzerland

Jenewein Thomas, IQC and University of Waterloo, Ontario, Canada

Predojevic Ana, Stockholm University, Sweden

Pullerits Tönu, Lund University, Sweden

Rastelli Armando, johannes Kepler University Linz, Austria

Reitzenstein Stefan, Technical University Berlin, Germany

Szameit Alexander, University of Rostock, Germany

Norbert Keil & Moritz Kleinert, Fraunhofer HHI Berlin, Germany

 

publications

Please find a detailed list of all our publications HERE

 

funding

The European Union   supports our research activities related to quantum technology / quantum communications through it's Horizon 2020 research and innovation programme: Quantum Flagship

 

The Austrian Science Fund    funds our work through the following projects

• SFB "Beyond-C", project "P14 - Integrated Quantum Photonics" (F 7114, together with IST Austria, University of Vienna, OEAW, Max-Planck-Institute for Quantum Optics in Garching, Germany)
  
• D-A-CH project "On-chip microlaser driven sources of indistinguishable photons for quantum networks" (I-5061, together with Tobias Huber, University of Würzburg and Stephan Reizenstein, University of Berlin)
• IGUANA - "Integrated Quantum Rangefinding" (Q 3)
• AEQuDot - "Advanced Entanglement from Quantum Dots" (I 4380, together with Doris Reiter, TU Dortmund and Armando Rastelli, University of Linz)
• DarkEneT - "Engineering Dark modes for Energy Trapping" (TAI 556 1000 Ideas Program)
• Project "Multiphoton Experiments with Semiconductor Quantum Dots", (FG 5)
  
• Doctoral Program "Atoms, Light and Molecules" (W-1259, Speaker: R. Wester)

Past funding can be found HERE