2019-04-11 Press Release

An international collaboration of researchers from University of Hamburg, Université libre de Bruxelles, and RIKEN iTHEMS observed quantized heating rate, demonstrating a novel universal probe for topological states of matter. The experiment was performed using a gas of ultracold potassium atoms. The researchers looked for the difference in heating rate upong "shaking" the system clock-wise and counter-clock-wise, and confirmed that this different is quantized to the value of the "Chern number" of the system, a topological invariant characterizing a two-dimensional system. The experiment took place in Hamburg, with theoretical collaborations from theorists in Bruxelles and RIKEN iTHEMS.


  1. Luca Asteria, Duc Thanh Tran, Tomoki Ozawa, Matthias Tarnowski, Benno S. Rem, Nick Fläschner, Klaus Sengstock, Nathan Goldman & Christof Weitenberg, Measuring quantized circular dichroism in ultracold topological matter, Nature Physics 15, 449–454 (2019), doi: 10.1038/s41567-019-0417-8

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