Extreme-Ultraviolet Vortices of very high Topological Charge

Pandey, Alok Kumar; Heras, Alba de las; Román, Julio San; Plaja, Luis; Baynard, Elsa; Dovillaire, Guillaume; Pittman, M.; Kazamias, S.; Guilbaud, Olivier; Hernández-García, Carlos

doi:10.1109/cleo/europe-eqec52157.2021.9542425

Cited by 1 publication

(1 citation statement)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, these approaches are computationally intensive and are inefficient for the reconstruction of dislocations of orders greater than four [ 58 ]. Therefore, instead of relying on these methods, we used a simplified approach that has successfully been used to reconstruct the wavefront of the vortex and vector-vortex beams exhibiting topological charge as high as 100 [ 65 , 66 , 67 ]. We purposefully introduced a discontinuity in the slopes map at an arbitrary position.…”

Section: Experimental Setup and Methods For Wavefront Characterization Of Ultrashort Vortex Beamsmentioning

confidence: 99%

Shack-Hartmann Wavefront Sensing of Ultrashort Optical Vortices

Pandey

Larrieu

Dovillaire

et al. 2021

Sensors

Self Cite

View full text Add to dashboard Cite

Light beams carrying Orbital Angular Momentum (OAM), also known as optical vortices (OV), have led to fascinating new developments in fields ranging from quantum communication to novel light–matter interaction aspects. Even though several techniques have emerged to synthesize these structured-beams, their detection, in particular, single-shot amplitude, wavefront, and modal content characterization, remains a challenging task. Here, we report the single-shot amplitude, wavefront, and modal content characterization of ultrashort OV using a Shack-Hartmann wavefront sensor. These vortex beams are obtained using spiral phase plates (SPPs) that are frequently used for high-intensity applications. The reconstructed wavefronts display a helical structure compatible with the topological charge induced by the SPPs. We affirm the accuracy of the optical field reconstruction by the wavefront sensor through an excellent agreement between the numerically backpropagated and experimentally obtained intensity distribution at the waist. Consequently, through Laguerre–Gauss (LG) decomposition of the reconstructed fields, we reveal the radial and azimuthal mode composition of vortex beams under different conditions. The potential of our method is further illustrated by characterizing asymmetric Gaussian vortices carrying fractional average OAM, and a realtime topological charge measurement at a 10Hz repetition rate. These results can promote Shack-Hartmann wavefront sensing as a single-shot OV characterization tool.

show abstract

Section: Experimental Setup and Methods For Wavefront Characterization Of Ultrashort Vortex Beamsmentioning

confidence: 99%