Robert Fickler

Dr. Robert Fickler is working in the field of quantum optics and photonics. After his apprenticeship as an electronics engineer he studied physics at the University of Ulm, Germany, where he did his Masters in the group of Prof. Schmidt-Kaler working on a deterministic ultra-cold ion source. Additionally, he received a Bachelor degree in Philosophy for which he investigated the term “realism” in quantum physics. For his PhD, he joined the group of Prof. Zeilinger at the University of Vienna and the Institute of Quantum Optics and Quantum Information in Vienna. There, he developed novel techniques to generate, investigate and test the entanglement of complex structures of photons. Among other things, this study led to the entanglement of the highest quantum number in experimental physics. Currently, Dr. Fickler is a postdoctoral fellow in the quantum photonics group where he is working with Prof. Boyd and Prof. Karimi on experiments to investigate novel properties of light to advance both, applications of quantum optics as well as to test its foundation.


University of Vienna / IQOQI Vienna, Austria, 2014 PhD (Dr. rer. nat)
University Of Ulm, Germany, 2009, MSc (Dipl. Phys.)
University Of Ulm, Germany, 2008, BA Phil.


  • Young Scientist Prize 2015 of the IUPAP (C17 – Laser Physics and Photonics) for out-standing contributions of a fundamental nature
  • Springer Thesis Award 2015 recognizing outstanding Ph.D. research
  • Award 2014 for outstanding doctoral theses (University of Vienna and City of Vienna)
  • Best Paper Award 2013 (City of Vienna) „Quantum entanglement of high angular momenta”
  • “Quantum entanglement of high angular momenta” named as one of the Top 10 breakthroughs of the year 2012 (IOP’s Physics World)


  1. Structured Quantum Projectiles, Physical Review A 99, 023628 (2019).
  2. Experimental realization of wave-packet dynamics in cyclic quantum walks, Optica 6, 174 (2019).
  3. Experimental investigation of high-dimensional quantum key distribution protocols with twisted photons, Quantum 2, 111 (2018).
  4. Reconstructing the topology of optical polarization knots, Nature Physics 14, 1079 (2018).
  5. Quantum cryptography with twisted photons through an outdoor underwater channel, Optics Express 26, 22563-22573 (2018).
  6. Quantum cryptography with structured photons through a vortex fiber, Optics Letters 43, 4108 (2018).
  7. Round-Robin Differential Phase-Shift Quantum Key Distribution with Twisted Photons, Physical Review 96, 010301(R) (2018).
  8. High-Dimensional Intra-City Quantum Cryptography with Structured Photons, Optica 4, 1006 (2017)
  9. Exotic Looped Trajectories of Photons in Three-Slit Interference, Nature Communications 7, 13987 (2016).
  10. Experimental ladder proof of Hardy’s nonlocality for high-dimensional quantum systems, Physical Review A 96, 022115 (2017).
  11. High-dimensional quantum cloning and applications to quantum hacking, Science Advances 3, e1601915  (2017).
  12. Roadmap on structured light, Journal of Optics 19, 013001 (2017).
  13. Twisted light transmission over 143 km, PNAS 113, 13648 (2016)
  14. Quantum entanglement of angular momentum states with quantum numbers up to 10,010, PNAS 113, 13642 (2016)
  15. Arbitrary optical wavefront shaping via spin-to-orbit coupling,  Journal of Optics 18, 124002 (2016).
  16. Quantum optical rotatory dispersion, Science Advances 2, e1601306 (2016).
  17. Finite-key security analysis for multilevel quantum key distribution, New Journal of Physics 18, 073030 (2016)
  18. Cyclic transformation of orbital angular momentum modes, New Journal of Physics 18, 043019 (2016)
  19. Automated Search for new Quantum Experiments, Physical Review Letters 116, 090405 (2016)
  20. Multi-photon entanglement in high dimensions, Nature Photonics 10, 248-252 (2016)
  21. Twisted photon entanglement through turbulent air across Vienna, PNAS 112, 14197-14201 (2015).
  22. Violation of an extended Wigner inequality with high-angular-momentum states, Physical Review A 91, 022124 (2015).
  23. Communication with spatially modulated light through turbulent air across Vienna, New Journal of Physics 16, 113028 (2014) – results summarized in a youtube video.
  24. Interface between path and orbital angular momentum entanglement for high-dimensional photonic quantum information, Nature Communications 5, 4502 (2014).
  25. Generation and confirmation of a (100× 100)-dimensional entangled quantum system, PNAS 111, 6243-6247 (2014).
  26. Quantum entanglement of complex photon polarization patterns in vector beams, Physical Review A 89, 060301(R) (2014).
  27. Real-time imaging of quantum entanglement, Scientific Reports 3, 1914 (2013).
    results summarized in a youtube video.
  28. Direct characterization of linear-optical networks, Optics Express 21, 13450-13458 (2013).
  29. Quantum orbital angular momentum of elliptically symmetric light, Physical Review A 87, 033806 (2013).
  30. Entangled singularity patterns of photons in Ince-Gauss modes, Physical Review A 87, 012326 (2013).
  31. Quantum entanglement of high angular momenta, Science 338, 640-643 (2012).
  32. Scalable fiber integrated source for higher-dimensional path-entangled photonic quNits, Optics Express 20, 16145-16153 (2012).
  33. Focusing a deterministic single-ion beam, New Journal of Physics 12, 065023 (2010).
  34. Optimised focusing ion optics for an ultracold deterministic single ion source targeting nm resolution, Journal of Modern Optics 56, 2061-2075 (2009).
  35. Deterministic ultracold ion source targeting the Heisenberg limit, Physical Review Letters 102, 70501 (2009).