Erlangen 2026 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MP: Fachverband Theoretische und Mathematische Grundlagen der Physik
MP 5: Quantum Mechanics: Spectral Theory and Many-Body Systems
MP 5.4: Vortrag
Mittwoch, 18. März 2026, 14:45–15:00, KH 02.013
Beyond the rotating-wave approximation: error bounds for higher order approximations — •Leonhard Richter1, Robin Hillier2, Davide Lonigro1, and Daniel Burgarth1 — 1Department of Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany — 2Department of Mathematics and Statistics, Lancaster University, UK
The rotating-wave approximation (RWA) is a widely used method for simplifying differential equations such as the Schrödinger equation in light-matter systems. However, its limitations have become more apparent with recent technological advancements highlighting the need for more sophisticated approximation schemes and quantitative estimates on the error introduced by empoying approximations. I will give an overview of error bounds for such approximation schemes with a focus on one particular drawback of the RWA: the error it introduces accumulates over time eventually rendering its application unjustified. In bounded semi-classical systems with time-periodic Hamiltonian the RWA is known to be the first order of the Floquet-Magnus expansion. Recently, an alternative perspective on this expansion allowed to provide explicit error bounds that capture the time-dependence of each order in the series reasonably well.
This talk is based on work by and with Anirban Dey, Davide Lonigro, Kazuya Yuasa, Robin Hillier, and Daniel Burgarth.
Keywords: rotating-wave approximation; Bloch-Siegert Hamiltonian; Floquet-Magnus; error bounds