Conservation of Torus-knot Angular Momentum in High-order Harmonic Generation

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 demonst...

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Bibliographic Details
Authors: Pisanty, Emilio, Rego Cabezas, Laura, San Román Álvarez de Lara, Julio, Picón, Antonio, Dorney, Kevin M., Kapteyn, Henry C., Murnane, Margaret M., Plaja Rustein, Luis, Lewenstein, Maciej, Hernández García, Carlos
Format: article
Status:Published version
Publication Date:2019
Country:España
Institution:Universidad de Salamanca (USAL)
Repository:GREDOS. Repositorio Institucional de la Universidad de Salamanca
OAI Identifier:oai:gredos.usal.es:10366/146644
Online Access:http://hdl.handle.net/10366/146644
Access Level:Open access
Keyword:Angular momentum of light
Nonlinear optics
Optical vortices
Polarization of light
Quantum description of light-matter interaction
Spin-orbit coupling
Strong-field-induced spectra
Ultrafast optics
Ultrafast phenomena
Ultrashort pulses
Description
Summary: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.