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Geometric Magnetism and New Enantio-Sensitive Observables in Photoionization of Chiral Molecules

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Geometric Magnetism and New Enantio-Sensitive Observables in Photoionization of Chiral Molecules Geometric magnetism and new enantio-sensitive observables in photoionization of chiral molecules Anders Ordonez1,2, David Ayuso1, Piero Decleva3, Olga Smirnova1,2 1Max-Born Institute, Max-Born Strasse 2a, 12489 Berlin, Germany 2Technical University Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany 3University of Trieste, Piazzale Europa, 1, 34127 Trieste TS, Italy Synopsis: We introduce a new phenomenon - enantio-sensitive orientation of chiral molecules via photoionization and uncover the new class of the efficient enantio-sensitive observables in photoionization associated with ultrafast excitation of chiral electronic or vibronic currents. Chiral molecules are instrumental for molecular class of efficient enantio-sensitive observables recognition in living organisms. Distinguishing emerging in non-linear photoionization. We formulate between two enantiomers, the mirror twins of the same the fundamental principles which allow one to predict chiral molecule, is both vital and challenging. the new enantio-sensitive observables. Crucially, the Photoelectron circular dichroism (PECD) is an emergence of these new observables is associated with extremely sensitive probe of molecular chirality, ultrafast excitation of chiral electronic or vibronic which outperforms standard optical methods by many currents prior to ionization and can be viewed as their orders of magnitude [1-9]. We show that the unique signature. To illustrate our concept we emergence of PECD can be linked to the concept of introduce a new phenomenon - enantio-sensitive geometric magnetism, which enables a broad class of orientation of chiral molecules via photoionization, phenomena in condensed matter systems including the opening the way to efficient enantio-separation and anomalous electron velocity and the Hall effect and molecular imaging on ultrafast time scales. Imaging of related topological phenomena [11]. Following this geometric field and new ultrafast enantio-sensitive link, we uncover geometric magnetic field in observables – messengers of charge -directed photoionization of chiral molecules and we show that photoreactivity is a new frontier in non-linear PECD is only a tip of the iceberg – the iceberg is a new photoionization. References [1] B. Ritchie, Theory of the angular distribution of in the photoionization of chiral molecules, New Journal of photoelectrons ejected from optically active moleculesand Physics 18, 102002 (2016). molecular negative ions, Phys. Rev. A 13, 1411 (1976). [9] A. Comby, S. Beaulieu, M. Boggio-Pasqua, D. Descamps, F. [2] I. Powis, Photoelectron circular dichroism of the randomly Légaré, L. Nahon, S. Petit, B. Pons, B. Fabre,Y. Mairesse, oriented chiral molecules glyceraldehyde andlactic acid, The and V. Blanchet, Relaxation dynamics in photoexcited chiral Journal of Chemical Physics 112, 301 (2000). molecules studied by time-resolved photoelectron circular [3] N. Böwering, T. Lischke, B. Schmidtke, N. Müller, T. dichroism: Toward chiral femtochemistry, The Journal of Khalil, and U. Heinzmann, Asymmetry in photo-electron Physical Chemistry Letters B, 4514 (2016) emission from chiral molecules induced by circularly [10] D. Xiao, M.-C. Chang, and Q. Niu, Berry phase effects on polarized light, Phys. Rev. Lett. 86, 1187 (2001). electronic properties, Rev. Mod. Phys. 82, 1959 (2010). [4] L. Nahon, G. A. Garcia, and I. Powis, Valence shell one- photon photoelectron circular dichroism in chiralsystems, Journal of Electron Spectroscopy and Related Phenomena 204, 322 (2015). [5] M. H. M. Janssen and I. Powis, Detecting chirality in molecules by imaging photoelectron circular dichroism, Phys. Chem. Chem. Phys. 16, 856 (2014). [6] C. Lux, M. Wollenhaupt, T. Bolze, Q. Liang, J. Köhler, C. Sarpe, and T. Baumert, Circular dichroismin the photoelectron angular distributions of camphor and fenchone from multiphoton ionization with femtosecond laser pulses, Angewandte Chemie International Edition 51, 5001 (2012). [7] C. S. Lehmann, N. B. Ram, I. Powis, and M. H. M. Janssen, Imaging photoelectron circular dichroismof chiral molecules by femtosecond multiphoton coincidence detection, The Journal of Chemical Physics 139, 234307 (2013). [8] S. Beaulieu, A. Ferré, R. Géneaux, R. Canonge, D. Descamps, B. Fabre, N. Fedorov, F. Légaré, S. Petit, T. Ru- chon,et al., Universality of photoelectron circular dichroism .
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