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The Role of Gauge Symmetries in the Discovery of Novel States of Condensed Matter
Jürg Fröhlich
em., ETH Zürich/IAS Princeton Cambridge, October 29, 2012
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A short summary of my lecture
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Credits: Bieri, Boyarsky, Cheianov, Graf, Kerler, Levkivskyi, Pedrini, Ruchayskyi, Schweigert, Studer, Sukhorukov, Thiran, Walcher, Werner, Zee – R. Morf Period of work: 1989/90 – 2012 (from postmodern to modern), with many interruptions
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Remarks on experimental realizations: - Spin quantum Hall effect observed in materials with strong spin-orbit coupling and “inverted band gap” Example: HgTe (Würzburg group – Molenkamp et al.) - 3D topological insulators realized in Bi2Te3 , Bi2Se3,, etc. (insulators with spin-orbit coupling and “inverted band gaps”; materials with magnetic fluctuations axionic topological insulators)
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- Cold atom gases in an effective external gauge field
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Some digressions for people in the audience interested in theory 1) Theoretical ideas
concerning the classification of incompressible Hall fluids exhibiting the quantum Hall effect; or
2) Higher-dimensional cousins of the quantum Hall effect, with applications to cosmology
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