We use cookies to improve the experience of our website.

I agree We use first-party and third-party cookies to improve the user experience on our website. You can disable the use of cookies by changing your browser settings (learn more). By continuing to browse the website without changing browser settings, you consent to our use of cookies stored on this device as described in our cookie policy.

DU Logo NU Logo

Rydberg Nonlinear Quantum Optics


Latest news

2017-10-12: Simon Ball passes PhD viva

Thesis title: "A coherent microwave interface for manipulation of single photons".

Title: "Contactless photon-photon interactions".

Teodora Ilieva wins poster prize at ICOLS 2017.

PhD student Teodora Ilieva has been selected to present the latest results of the Rydberg Nonlinear Quantum Optics project on "Contactless Nonlinear Optics with Cold Rydberg Atoms" in a hot topics talk at ICOLS 2017.

Thesis title: "Contactless quantum non-linear optics with cold Rydberg atoms".


See all news

Latest publications


See full list of publications

Project overview

The lack of intrinsic interactions between optical photons combined with the ability to control the propagation of photons using optics makes them ideal carriers of information. At the same time, the lack of interactions makes processing of the encoded information at the level of individual quanta difficult. In conventional nonlinear optics, nonlinearities become apparent  only at very high intensities. The Rydberg Nonlinear Quantum Optics project focusses on the creation of strong optical nonlinearities and effective interactions at the level of individual photons by interfacing optical photons with ultracold Rydberg atoms [1-3] confined in magneto-optical (MOT) and optical dipole traps, which exhibit strong dipolar interactions over distances of many micrometers.

To achieve a coherent mapping of the strong interactions between collective atomic Rydberg excitations [4] as well as the resulting effects such as dipole (or Rydberg) blockade [5], which permits only a single Rydberg excitation within a region of a few micrometers, onto optical photons, we are using quantum optical techniques such as electromagnetically induced transparency (EIT) and photon storage [6,7]. A brief introduction to the underlying concepts of Rydberg Nonlinear Quantum Optics can be found on our background pages.

We are interested in exploiting the mapping and the resulting nonlinearities for applications in quantum optics, quantum simulation, optical quantum information processing, and interfacing of optical photons with microwave fields. At the same time, we are also investigating the fundamental physics and collective behaviour of strongly interacting atomic dipoles ranging from the optical to the microwave regime.

Following the first experimental demonstration of a giant optical nonlinearity here at Durham [8] and the subsequent generation of highly non-classical states of light [9-11], Rydberg Quantum Nonlinear Optics is flourishing, and a variety of single photon devices have been realised [2]. One of the most recent highlights of our work is the demonstration of a "contactless" interaction between photons [12] that are stored as collective Rydberg excitations in separate cold atom clouds and propagate in non-overlapping optical media. The interaction occurs over distances of more than 10 μm, well above the optical diffration limit. You can find out more on our results pages.

An overview of our experimental setup [13], which provides optical resolution on the order of 1 μm thanks to the incorporation of in-vacuo aspheric lenses and allows to perform experiments at effective repetition rates of about 150 kHz to acquire large datasets for the analysis of photon statistics, can be found here.


* indicates work by our group 

  • *[1] J. D. Pritchard, K. J. Weatherill, and C. S. Adams, “Nonlinear optics using cold Rydberg atoms”, Ann. Rev. Cold At. Mol. 1, 301–350 (2013).

  • *[2] O. Firstenberg, C. S. Adams, and S. Hofferberth, “Nonlinear quantum optics mediated by Rydberg interactions”, J. Phys. B: At. Mol. Opt. Phys. 49, 152003 (2016).

  • [3] C. Murray and T. Pohl, “Quantum and Nonlinear Optics in Strongly Interacting Atomic Ensembles”, Adv. At. Mol. Opt. Phys. 65, 321–372 (2016).

  • [4] M. Saffman, T. G. Walker, and K. Mølmer, “Quantum information with Rydberg atoms”, Rev. Mod. Phys. 82, 2313–2363 (2010).

  • [5] M. D. Lukin, M. Fleischhauer, R. Côté, L. M. Duan, D. Jaksch, J. I. Cirac, and P. Zoller, “Dipole Blockade and Quantum Information Processing in Mesoscopic Atomic Ensembles”, Phys. Rev. Lett. 87, 037901 (2001).

  • [6] M. Fleischhauer, A. Imamoglu, and J. P. Marangos, “Electromagnetically induced transparency: Optics in coherent media”, Rev. Mod. Phys. 77, 633–673 (2005).

  • [7] M. Fleischhauer and M. D. Lukin, “Dark-State Polaritons in Electromagnetically Induced Transparency”, Phys. Rev. Lett. 84, 5094–5097 (2000).

  • *[8] J. D. Pritchard, D. Maxwell, A. Gauguet, K. J. Weatherill, M. P. A. Jones, and C. S. Adams, “Cooperative Atom-Light Interaction in a Blockaded Rydberg Ensemble”, Phys. Rev. Lett. 105, 193603 (2010).

  • [9] Y. O. Dudin and A. Kuzmich, “Strongly Interacting Rydberg Excitations of a Cold Atomic Gas”, Science 336, 887–889 (2012).

  • [10] T. Peyronel, O. Firstenberg, Q.-Y. Liang, S. Hofferberth, A. V. Gorshkov, T. Pohl, M. D. Lukin, and V. Vuletić, “Quantum nonlinear optics with single photons enabled by strongly interacting atoms”, Nature 448, 57–60 (2012).

  • *[11] D. Maxwell, D. J. Szwer, D. Paredes-Barato, H. Busche, J. D. Pritchard, A. Gauguet, K. J. Weatherill, M. P. A. Jones, and C. S. Adams, “Storage and Control of Optical Photons Using Rydberg Polaritons”, Phys. Rev. Lett. 110, 103001 (2013).

  • *[12] H. Busche, P. Huillery, S. W. Ball, T. V. Ilieva, M. P. A. Jones, and C. S. Adams, “Contactless non-linear optics mediated by long-range Rydberg interactions”, Nat. Phys. 13, 655–658 (2017).

  • *[13] H. Busche, S. W. Ball, and P. Huillery, “A high repetition rate experimental setup for quantum non-linear optics with cold Rydberg atoms”, Eur. Phys. J. Spec. Top. 225, 2839–2861 (2016).


We gratefully acknowledge funding from the following sources.

  • European Union (FP7 and Horizon 2020 programmes)

  • Engineering and Physical Research Council (EPSRC) grants

    • "Rydberg soft matter" (EP/M014398/1, since 2015)

    • "Dynamics of superatom quantum dots: single photon emission" (EP/H002839/1, 2009-2014)

    • "Photonic phase gates using Rydberg dark states" (EP/F040253/1, 2008-2012)

  • Durham University

  • Defence Science and Technology Laboratory (DSTL)