Im Neuenheimer Feld 226
Tel: 06221/ 54 19471
Fax: 06221/ 54 19545
"On the use and abuse of *thermodynamic* entropy"
Prof. Dr. Peter Hänggi
Strongly-correlated Rydberg quantum gases
Ultracold atomic gases are ideally suited for exploring the quantum physics of many-body systems and for investigating quantum matter and exotic quantum phenomena. We make use of the extraordinary properties of highly-excited Rydberg atoms in dense atomic gases to explore the realm of strongly-correlated many-body physics.
Ultracold Rydberg gases
For more than a century, atoms excited to high lying Rydberg states have been subject to research in many different fields because of their unique quantum mechanical properties. For example, due to their large polarizabilities, Rydberg atoms are extremely sensitive to external fields and can interact very strongly, even over macroscopic distances. By combining laser cooling and trapping of atoms with the coherent excitation of Rydberg atoms from dense atomic gases we are entering a new era of Rydberg physics. Of particular interest, the typical interaction ranges between Rydberg atoms are comparable to, or larger than, the typical interatomic separations in a Bose-Einstein condensate (BEC), which creates new possibilities to control atomic interactions in quantum gases and can lead to new strongly-correlated phases of matter.
A long standing focus of the Quantum Dynamics group has been on coherent excitation of Rydberg atoms, and the dramatic effects caused by strong Rydberg-Rydberg interactions. See for example our recent results on interaction induced imaging of single atoms and coherent population trapping involving excited Rydberg states.
We have built a new experiment, aimed at studying ultracold Rydberg atoms in dense atomic gases. Our new system possesses excellent optical access for creating optical dipole traps and optical lattices, combined with great control over electric fields necessary for the study of strongly interacting Rydberg atoms. Key aspects include all-optical evaporation, a compact two-dimensional MOT (2DMOT) as a cold atom source, and a new single atom sensitive Rydberg detector, which includes sensitive ion detectors and a system of 8 individually addressable electrodes capable of generating virtually any electric field configuration. With this new system we will have complete access to the microscopic properties of interacting Rydberg systems, allowing for new studies of novel quantum phases, collective properties and entanglement in complex many-body systems.
Latest news and research results
|Review of the EU Training Network on Rydberg physics published as a special issue of the EPJ||04.01.2017|
For more information:
|Interaction Enhanced Imaging of Rydberg P states published in Eur. Phys. J. Special Topics!||19.12.2016|
We experimentally realize fast and efficient threephoton excitation of P states, optimized according to the results of a theoretical effective two-level model. Few Rydberg P-state atoms, prepared in a small cloud with dimensions comparable to the blockade radius, are detected with a good sensitivity by averaging over 50 shots. The main aspects of the technique are described with a hard sphere model, finding good agreement with experimental data. This work paves the way to a non-destructive optical detection of single Rydberg atoms with high spatial and temporal resolution.
Interaction Enhanced Imaging of Rydberg P states: Preparation and detection of Rydberg atoms for engineering long-range interactions, Eur. Phys. J. Special Topics 225, 2863–2889 (2016), or see our full list of publications
|Vladislav Gavryusev is now Dr. V. Gavryusev!||19.12.2016|
Afterwards he received his PhD hat (see picture). The hat came with a replica of one of the lasers used in the Rydberg experiment. Vladislav had to lock the laser to a little cavity and align it to the center of a mini-vacuum chamber (which was actually at room pressure...). Afterwards Vlad had to proof his german and dancing skills. In the end he mastered all the tasks his hat had to offer and now truly deserves his PhD!
Imaging of Rydberg Impurities in an Ultracold Atomic Gas, PhD thesis, or see our full list of publications
Publications by the Rydberg project
Density matrix reconstruction of three-level atoms via Rydberg electromagnetically induced transparency, Journal of Physics B: Atomic, Molecular and Optical Physics 49, 164002 (2016) [pdf]
Interaction Enhanced Imaging of Rydberg P states, The European Physical Journal Special Topics 225, 2863-2889 (2016) [pdf]
2015 Correlated Exciton Transport in Rydberg-Dressed-Atom Spin Chains, Phys. Rev. Lett. 115, 093002 (2015) [pdf]
2014 Full Counting Statistics of Laser Excited Rydberg Aggregates in a One-Dimensional Geometry, Phys. Rev. Lett. 112, 013002 (2014)
An experimental approach for investigating many-body phenomena in Rydberg-interacting quantum systems, Frontiers of Physics 9, 571-586 (2014)
2013 Observing the Dynamics of Dipole-Mediated Energy Transport by Interaction-Enhanced Imaging, Science 342, 954-956 (2013)
Spontaneous avalanche ionization of a strongly blockaded Rydberg gas, Phys. Rev. Lett. 110, 045004 (2013) [pdf]
Atomic Interactions at a Distance, Physics 6, 71 (2013) [pdf]
Quantum physics: Spooky action gets collective, Nature 498, 438 (2013)
Sub-Poissonian Statistics of Rydberg-Interacting Dark-State Polaritons, Phys. Rev. Lett. 110, 203601 (2013) [pdf]
2012 Interaction enhanced imaging of individual atoms embedded in dense atomic gases, Phys. Rev. Lett 108, 013002 (2012) [pdf]
2011 Quantum interference in interacting three-level Rydberg gases: coherent population trapping and electromagnetically induced transparency, J. Phys. B: At. Mol. Opt. Phys. 44, 184018 (2011) [pdf]
High-precision semiconductor wavelength sensor based on a double-layer photo diode, Review of Scientific Instruments 82, 093111 (2011)
2010 Coherent population trapping with controlled interparticle interactions, Phys. Rev. Lett. 104, 173602 (2010)
Evidence of Antiblockade in an Ultracold Rydberg Gas, Phys. Rev. Lett. 104, 013001 (2010)
2009 Rydberg atoms - There can be only one, Nature Physics 5 (2009)
Autoionization of an ultracold Rydberg gas through resonant dipole coupling, Eur. Phys. J. D 53, 329 (2009)
Frozen Rydberg Gases, in: Cold Atoms and Molecules, Wiley VCH (2009)
2008 Rabi oscillations between ground and Rydberg states and van der Waals blockade in a mesoscopic frozen Rydberg gas, New J. Phys. 10, 045026 (2008)
2007 Modeling few-body phenomena in an ultracold Rydberg gas, Nucl. Phys. A 790, 728c (2007)
Mechanical effect of van der Waals interactions observed in real time in an ultracold Rydberg gas, Phys. Rev. Lett. 98, 023004 (2007)
2006 Coherent excitation of Rydberg atoms in an ultracold gas, Opt. Comm. 264, 293 (2006)
Prospects of ultracold Rydberg gases for quantum information processing, Fortschr. Phys. 54, 776 (2006)
Motion in an ultralong-range potential in cold-Rydberg-atom collisions, Phys. Rev. A 73, 034703 (2006)
2005 Long-range interactions between alkali Rydberg atom pairs correlated to the ns-ns, np-np and nd-nd asymptotes, J. Phys. B 38, S295 (2005)
Spectroscopy of an ultracold Rydberg gas and signatures of Rydberg-Rydberg interactions, J. Phys. B 38, S321 (2005)
Ultralong-Range Interactions and Blockade of Excitation in a Cold Rydberg Gas, in: Atomic Physics XIX, pp. 157-163 (2005)
Interactions in an Ultracold Gas of Rydberg Atoms, in: Laser Spectroscopy XVII, pp. 264-274 (2005)
2004 Spectral Broadening and Suppression of Excitation Induced by Ultralong-Range Interactions in a Cold Gas of Rydberg Atoms, Phys. Rev. Lett. 93, 163001 (2004)