1. Conservation of Torus-knot Angular Momentum in High-order Harmonic Generation
- Author
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Carlos Hernandez-Garcia, Maciej Lewenstein, Luis Plaja, Kevin M. Dorney, Laura Rego, Margaret M. Murnane, Antonio Picón, Emilio Pisanty, Henry C. Kapteyn, and Julio San Roman
- Subjects
Angular momentum ,Nonlinear optics ,Atomic Physics (physics.atom-ph) ,FOS: Physical sciences ,General Physics and Astronomy ,Polarization of light ,Strong-field-induced spectra ,01 natural sciences ,Physics - Atomic Physics ,Ultrafast optics ,Ultrashort pulses ,Quantum description of light-matter interaction ,0103 physical sciences ,Angular momentum of light ,High harmonic generation ,Spin-orbit coupling ,010306 general physics ,Optical vortices ,Physics ,Quantum Physics ,Conservation law ,Spin–orbit interaction ,Ultrafast phenomena ,Quantum electrodynamics ,Harmonics ,Quantum Physics (quant-ph) ,Optical vortex ,Optics (physics.optics) ,Physics - Optics - Abstract
High-order harmonic generation stands as a unique nonlinear optical up-conversion process, mediated by a laser-driven electron recollision mechanism, which has been shown to conserve energy, linear momentum, and spin and orbital angular momentum. Here, we present theoretical simulations that demonstrate that this process also conserves a mixture of the latter, the torus-knot angular momentum Jγ, by producing high-order harmonics with driving pulses that are invariant under coordinated rotations. We demonstrate that the charge Jγ of the emitted harmonics scales linearly with the harmonic order, and that this conservation law is imprinted onto the polarization distribution of the emitted spiral of attosecond pulses. We also demonstrate how the nonperturbative physics of high-order harmonic generation affect the torus-knot angular momentum of the harmonics, and we show that this configuration harnesses the spin selection rules to channel the full yield of each harmonic into a single mode of controllable orbital angular momentum., We thank T. Ruchon for helpful observations. E. P. acknowledges Cellex-ICFO-MPQ fellowship funding; E. P. and M. L. acknowledge the Spanish Ministry MINECO (National Plan 15 Grants: FISICATEAMO No. FIS2016-79508-P, SEVERO OCHOA No. SEV-2015-0522, FPI), European Social Fund, Fundació Cellex, Generalitat de Catalunya (AGAUR Grant No. 2017 SGR1341 and CERCA/Program), ERC AdG OSYRIS, EU FETPRO QUIC, and the National Science Centre, Poland-Symfonia Grant No. 2016/20/W/ST4/00314. A. P. acknowledges funding from Comunidad de Madrid through TALENTO Grant No. 2017-T1/IND-5432. J. S. R., L. P., and C. H.-G acknowledge support from Junta de Castilla y León (SA046U16) and Ministerio de Economía y Competitividad (FIS2013-44174-P, FIS2016-75652-P). C. H.-G. acknowledges support from a 2017 Leonardo Grant for Researchers and Cultural Creators, BBVA Foundation and Ministerio de Ciencia, Innovación y Universidades for a Ramón y Cajal contract (RYC-2017-22745), co-funded by the European Social Fund. L. R. acknowledges support from Ministerio de Educación, Cultura y Deporte (FPU16/02591). H. C. K. and M.M.M. acknowledge support from the Department of Energy BESAwardNo.DE-FG02–99ER14982, as well as aDARPATEE Award No. D18AC00017. We thankfully acknowledge thecomputer resources at MareNostrum and the technical support provided by Barcelona Supercomputing Center (RES-AECT-2014-2-0085). This research made use of the high-performance computing resources of the Castilla yLeón Supercomputing Center (SCAYLE), financed by the European Regional Development Fund (ERDF).
- Published
- 2019