Radial index of Laguerre-Gaussian modes in high-order-harmonic generation

Romain Géneaux (1, 2) , Céline Chappuis (2, 1) , Thierry Auguste (1, 2) , Samuel Beaulieu (3, 4) , Timothy T. Gorman (5) , Fabien Lepetit (2, 6) , Louis F. Dimauro (5) , Thierry Ruchon (1, 2)

1 ATTO - Attophysique
2 LIDyl - Laboratoire Interactions, Dynamiques et Lasers (ex SPAM)
3 CELIA - Centre d'Etudes Lasers Intenses et Applications
4 INRS - Institut National de la Recherche Scientifique [Québec]
5 OSU - Ohio State University [Columbus]
6 SLIC - Serveurs Laser

High-order-harmonic generation (HHG) is a tabletop and tunable source of extreme ultraviolet (XUV) light. Its flexibility was lately evidenced by the production of Laguerre-Gaussian (LG) modes in the XUV with a known azimuthal index. Here we investigate the role of the radial index of LG modes in HHG. We show both numerically and experimentally that the mode content of the emitted XUV radiation can be tuned by controlling the weight of the different quantum trajectories involved in the process. The appearance of high-order radial modes is finally linked to the atomic dipole phase of HHG. These results extend the capabilities of shaping the spatial mode of ultrashort XUV pulses of light.

Domains: Physics [physics]

Romain Géneaux, Céline Chappuis, Thierry Auguste, Samuel Beaulieu, Timothy T. Gorman, et al.. Radial index of Laguerre-Gaussian modes in high-order-harmonic generation . Physical Review A : Atomic, molecular, and optical physics, 2017, 95 (5), pp.051801(R). ⟨10.1103/PhysRevA.95.051801⟩. ⟨cea-01571633⟩