Circular Dichroism in the Multi-Photon Ionization of Oriented Helium Ions

[摘要] Synopsis Intense, circularly polarized extreme-ultraviolet (XUV) and near-infrared (NIR) laser pulses are combined to doubleionize atomic helium via the oriented intermediate He+(3p) resonance state. A strong and NIR-intensity dependent circular dichroism is accounted to a helicity dependent AC-Stark shift.

[发布机构] European XFEL GmbH, Holzkoppel 4, Schenefeld Hamburg; 22869, Germany^1;PULSE at Stanford, 2575 Sand Hill Road, Menlo Park; CA; 94025, United States^2;Department of Physics and Astronomy, Drake University, Des Moines; IA; 50311, United States^3;Elettra-Sincrotrone Trieste, Basovizza; 34149, Italy^4;Istituto Officina Dei Materiali, Consiglio Nazionale Delle Ricerche, Area Science Park, Trieste; 34149, Italy^5;Molecular Model Discovery Laboratory, Department of Chemistry and Biotechnology, Swinburne University of Technology, Melbourne; VIC; 3122, Australia^6;CNR Istituto Struttura della Materia, Via del Fosso del Cavaliere, Roma; 100-00133, Italy^7;Department of Physics, University of Trieste, Trieste; 34128, Italy^8;Istituto di Fotonica e Nanotecnologie CNR-IFN, Milano, Italy; (10) Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, Hamburg; 22603, Germany; (11) Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai; 980-8577, Japan; (12) Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow; 119991, Russia; (13) Sankt Petersburg State University, Universitetskaya nab. 7/9, Sankt Petersburg; 199164, Russia; (14) Departamento de Fisica de Materiales, UPV/EHU, San Sebastian/Donostia; 25018, Spain; (15) IKERBASQUE, Basque Foundation for Science, Bilbao; 48011, Spain; (16) Donostia International Physics Center (DIPC), San Sebastian/Donostia; 25018, Spain^9

[关键词] AC Stark shift;Atomic helium;Circularly polarized;Extreme ultraviolets;Intensity-dependent;Multiphoton ionization;Near-infrared lasers;Resonance state