Observation of dipolar supersolids
(University of Stuttgart, Pfau Lab, 2016-2023)

First observation of a supersolid state of matter and its elementary excitations, coherence and superfluidity using dysprosium atoms. Observation of anisotropic superfluidity and imaging of dipolar rotons.

Highlights:

• Dipolar Supersolids: Solid and superfluid at the same time
  T. Langen
  Physics Today 75, 3, 36 (2022)
• Density Fluctuations across the Superfluid-Supersolid Phase Transition in a Dipolar Quantum Gas
  J. Hertkorn, J.-N. Schmidt, F. Böttcher, M. Guo, M. Schmidt, K.S.H. Ng, S.D. Graham, H.P. Büchler, T. Langen, M. Zwierlein, and T. Pfau
  Phys. Rev. X 11, 011037 (2021)
  
• The low-energy Goldstone mode in a trapped dipolar supersolid
  M. Guo, F. Böttcher, J. Hertkorn, J. Schmidt, M. Wenzel, H.P. Büchler, T. Langen, and T. Pfau
  Nature 574, 386–389 (2019)
  
• Transient supersolid properties in an array of dipolar quantum droplets
  F. Böttcher, J.-N. Schmidt, M. Wenzel, J. Hertkorn, M. Guo, T. Langen, and T. Pfau
  Phys. Rev. X 9, 011051 (2019)
  
  
• Rudolf Kaiser Prize 2019 for Tim Langen
• Heraeus Dissertation Prize 2020 for Fabian Boettcher
• Quantum Creators Prize 2022 for Jens Hertkorn
• APS Physics Highlights 2019
• Physical Review X 10th Anniversary Highlight
  

Direct cooling and trapping of hydroxyl radicals, Stark deceleration.

Highlights:

• Controlling spin flips of molecules in an electromagnetic trap
  D.L. Reens, H. Wu, T. Langen, and J. Ye
  Phys. Rev. A 96, 063420 (2017), arxiv:1706.02806
• Enhancing radical molecular beams by skimmer cooling
  H. Wu, D. Reens, T. Langen, Y. Shagam, D. Fontecha, and J. Ye
  Phys. Chem. Chem. Phys. 20, 11615 (2018), arxiv:1802.10179
  

Non-equilibrium dynamics of one-dimensional Bose gases

(TU Wien, Schmiedmayer Lab, 2009-2014)

Highlights:

• Experimental characterization of a quantum many-body system via higher-order correlations
  T. Schweigler, V. Kasper, S. Erne, I. Mazets, B. Rauer, F. Cataldini, T. Langen,
  T. Gasenzer, J. Berges, and J. Schmiedmayer
  Nature 545, 323–326 (2017)
  
• Experimental observation of a generalized Gibbs ensemble
  T. Langen, S. Erne, R. Geiger, B. Rauer, T. Schweigler, M. Kuhnert, W. Rohringer, I. E. Mazets, T. Gasenzer, and J. Schmiedmayer
  Science 348, 207 (2015), arXiv:1411.7185
• Local emergence of thermal correlations in an isolated quantum many-body system
  T. Langen, R. Geiger, M. Kuhnert, B. Rauer, and J. Schmiedmayer
  Nature Physics 9, 640–643 (2013), arxiv:1305.3708
  
• Relaxation and prethermalization in an isolated quantum system
  M. Gring, M. Kuhnert, T. Langen, T. Kitagawa, B. Rauer, M. Schreitl, I. Mazets, D. Adu Smith, E. Demler, and J. Schmiedmayer
  Science 337, 1318 (2012), arXiv:1112.0013
• Non-equilibrium dynamics of one-dimensional Bose gases
  T. Langen
  PhD Thesis, Technical University of Vienna, Austria (2013)
  
  

• 2017 NJP Early Career Award (Runner Up) for Tim Langen
• 2015 European Physical Society QEOD Thesis Award for Tim Langen
• Springer Theses Award for Tim Langen
• Best of Wissenschaft 2012
  

Ultracold bosonic gases of Lithium 6 in the unitary limit

Highlight:

• Lifetime of the Bose gas with resonant interactions
  B. Rem, A. Grier, I. Ferrier-Barbut, U. Eismann, T. Langen, N. Navon, L. Khaykovich, F. Werner, D. Petrov, F. Chevy, and C. Salomon
  Phys. Rev. Lett. 110, 163202 (2013), arXiv:1212.5274
  

First imaging and addressing of single sites in an optical lattice.

Highlights: 

• High resolution scanning electron microscopy of an ultracold quantum gas
  T. Gericke, P. Würtz, D. Reitz, T. Langen, and H. Ott
  Nature Physics 4, 949 – 953 (2008)
• Experimental demonstration of single-site addressability in a two-dimensional optical lattice
  P. Würtz, T. Langen, T. Gericke, A. Koglbauer, and H. Ott
  Phys. Rev. Lett. 103, 080404 (2009)
• Addressing of ultracold atoms in optical lattices
  T. Langen
  Diplomarbeit, Johannes Gutenberg-Universität Mainz, Germany (2008)