Spatio-temporal dynamics in nondiffractive Bessel ultrafast laser nanoscale volume structuring

Praveen Kumar Velpula; Manoj Bhuyan; François Courvoisier; Hao Zhang; Jean-Philippe Colombier; Razvan Stoian

Spatio-temporal dynamics in nondiffractive Bessel ultrafast laser nanoscale volume structuring

Praveen Kumar Velpula ¹ Manoj Bhuyan ¹ François Courvoisier ² Hao Zhang ¹ Jean-Philippe Colombier ¹ Razvan Stoian ¹

1 LHC - Laboratoire Hubert Curien [Saint Etienne]

2 FEMTO-ST - Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174)

Abstract : Thumbnail image of graphical abstract Nondiffractive ultrafast optical beams with quasi-stationary characteristics enable new regimes and scales in light-matter interactions. We discuss the action of ultrashort Bessel laser beams in bulk fused silica, emphasizing excitation dynamics with energy localization beyond diffraction limit. We shed light on relaxation channels leading to one-dimensional structures with nanoscale sections and morphologies ranging from densified matter to nanosized cavities. Space- and time-resolved absorption and phase-contrast microscopy reveals two main carrier relaxation paths. Fast exciton trapping in self-induced matrix deformations results in positive index contrast driven by swift accumulation of non-bridging oxygen hole centers and defect-driven structural rearrangements. High excitation densities determine thermomechanical paths, with onset of phase transitions and the release of pressure waves. High-aspect-ratio nanosized channels are thus created via rarefaction and liquid cavitation, accompanied by molecular decomposition and generation of oxygen deficiency. The characteristic electronic relaxation identifies the nature of structural transitions up to the onset of phase transformation. Temporal pulse dispersion regulation allows driving unique carrier dynamics with precise control over energy deposition down to the 100 nm scale. Extreme high-aspect-ratio uniform void structures can thus be fabricated in conditions of sub-micron transverse light confinement

Keywords : Non-diffractive Bessel beams ultrafast laser nanostructuring

Document type :

Journal articles

Domain :

Engineering Sciences [physics] / Optics / Photonic

Complete list of metadatas

https://hal-ujm.archives-ouvertes.fr/ujm-01346653
Contributor : Razvan Stoian <>
Submitted on : Tuesday, July 19, 2016 - 1:56:38 PM
Last modification on : Thursday, July 26, 2018 - 1:10:44 AM

Spatio-temporal dynamics in nondiffractive Bessel ultrafast laser nanoscale volume structuring

Identifiers

Collections

Citation

Export

Metrics

106

Contact

Spatio-temporal dynamics in nondiffractive Bessel ultrafast laser nanoscale volume structuring

Identifiers

Collections

Citation

Export

Share

Metrics

106

Contact