@article{f87d175e283a481ca808d86fa0b23553,
title = "Circular Dichroism in Multiphoton Ionization of Resonantly Excited He+ Ions",
abstract = "Intense, circularly polarized extreme-ultraviolet and near-infrared (NIR) laser pulses are combined to double ionize atomic helium via the oriented intermediate He+(3p) resonance state. Applying angle-resolved electron spectroscopy, we find a large photon helicity dependence of the spectrum and the angular distribution of the electrons ejected from the resonance by NIR multiphoton absorption. The measured circular dichroism is unexpectedly found to vary strongly as a function of the NIR intensity. The experimental data are well described by theoretical modeling and possible mechanisms are discussed.",
author = "M. Ilchen and N. Douguet and T. Mazza and Rafipoor, {A. J.} and C. Callegari and P. Finetti and O. Plekan and Prince, {K. C.} and A. Demidovich and C. Grazioli and L. Avaldi and P. Bolognesi and M. Coreno and {Di Fraia}, M. and M. Devetta and Y. Ovcharenko and S. D{\"u}sterer and K. Ueda and K. Bartschat and Grum-Grzhimailo, {A. N.} and Bozhevolnov, {A. V.} and Kazansky, {A. K.} and Kabachnik, {N. M.} and M. Meyer",
note = "Funding Information: The authors acknowledge the invaluable support of the technical and scientific staff of FERMI at Elettra-Sincrotrone Trieste. We also thank J. Viefhaus, DESY, for fruitful discussions. M.I. acknowledges funding from the Volkswagen Foundation, M.I. and A.J.R. received financial support from SFB 925 Light induced dynamics and control of correlated quantum systems at the University of Hamburg, T.M. and M.M. acknowledge financial support by Elettra within the CALIPSO Transnational Access Programme, and N.M.K. was supported by the European XFEL, DIPC, and the programme Physics with Accelerators and Reactors in Western Europe of the Russian Ministry of Education and Science. A.N.G. acknowledges support by the European XFEL. N.D. and K.B. acknowledge funding by the United States National Science Foundation under Grant No.PHY-1403245 and the XSEDE supercomputer allocation No.PHY-090031 to access Stampede at the Texas Advanced Computing Center and SuperMIC at Louisiana State University. Publisher Copyright: {\textcopyright} 2017 American Physical Society.",
year = "2017",
month = jan,
day = "5",
doi = "10.1103/PhysRevLett.118.013002",
language = "English",
volume = "118",
journal = "Physical Review Letters",
issn = "0031-9007",
publisher = "American Physical Society",
number = "1",
}