2026-06-03T13:58:47Zhttps://www.radar-service.eu/oai/OAIHandler

10.58160/stAWtPUnpVRsOspy2026-04-24T07:50:14Z

10.58160/stAWtPUnpVRsOspy Jayachandran, Ajay Ajay Jayachandran 0000-0002-5265-0502 University of Würzburg Müller, Stefan Stefan Müller 0009-0002-6384-9282 University of Würzburg University of Würzburg 2024 2024 Physics Chemistry Multidimensional spectroscopy Phase cycling Fluorescence Open Access Creative Commons Attribution 4.0 International Müller, Stefan 0009-0002-6384-9282 Jayachandran, Ajay 0000-0002-5265-0502 Brixner, Tobias 0000-0002-6529-704X Brixner, Tobias 0000-0002-6529-704X University of Würzburg An integral procedure in every coherent multidimensional spectroscopy experiment is to suppress undesired background signals. For that purpose, one can employ a particular phase-matching geometry or phase cycling, a procedure that was adapted from nuclear magnetic resonance (NMR) spectroscopy. In optical multidimensional spectroscopy, phase cycling has been usually carried out in a “nested” fashion, where pulse phases are incremented sequentially with linearly spaced increments. Another phase-cycling approach which was developed for NMR spectroscopy is “cogwheel phase cycling,” where all pulse phases are varied simultaneously in increments defined by so-called “winding numbers”. Here we explore the concept of cogwheel phase cycling in the context of population-based coherent multidimensional spectroscopy. We derive selection rules for resolving and extracting fourth-order and higher-order nonlinear signals by cogwheel phase cycling and describe how to perform a numerical search for the winding numbers for various population-detected 2D spectroscopy experiments. We also provide an expression for a numerical search for nested phase-cycling schemes and predict the most economical schemes of both approaches for a wide range of nonlinear signals. The signal selectivity of the technique is demonstrated experimentally by acquiring rephasing and nonrephasing fourth-order signals of a laser dye by both phase-cycling approaches. We find that individual nonlinear signal contributions are, in most cases, captured with fewer steps by cogwheel phase cycling compared to nested phase cycling. en 10.1063/5.0233694 European Research Council https://ror.org/0472cxd90 101141366 Isolating Many-Particle Correlations in Time and Space application/x-tar