2014/08/08 by P. Schattschneider, Th. Schachinger, Michael Stöger‐Pollach +9 · 1 citation
Physics and Astronomy · #Condensed matter physics #Electron #Fermi gas #Gyroradius #Landau damping #Landau quantization #Magnetic field #Mechanical and Optical Resonators #Physics #Quantum #Quantum Hall effect #Quantum and electron transport phenomena #Quantum mechanics #Quantum optics and atomic interactions #Quantum oscillations #cond-mat.mes-hall #physics.optics #quant-ph
paper · pdf · doi:10.1038/ncomms5586
published as Nature Commun. 5, 4586 (2014) · 10 pages, 4 figures
arxiv created 2014/08/08 · openalex publication_date 2014/08/08 · arxiv updated 2015/06/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Landau levels and states of electrons in a magnetic field are fundamental quantum entities underlying the quantum Hall and related effects in condensed matter physics. However, the real-space properties and observation of Landau wave functions remain elusive. Here we report the real-space observation of Landau states and the internal rotational dynamics of free electrons. States with different quantum numbers are produced using nanometre-sized electron vortex beams, with a radius chosen to match the waist of the Landau states, in a quasi-uniform magnetic field. Scanning the beams along the propagation direction, we reconstruct the rotational dynamics of the Landau wave functions with angular frequency ~100 GHz. We observe that Landau modes with different azimuthal quantum numbers belong to three classes, which are characterized by rotations with zero, Larmor and cyclotron frequencies, respectively. This is in sharp contrast to the uniform cyclotron rotation of classical electrons, and in perfect agreement with recent theoretical predictions.