Nanoscale reshaping of resonant dielectric microstructures by light-driven explosions

Maxim R Shcherbakov; Giovanni Sartorello; Simin Zhang; Joshua Bocanegra; Melissa Bosch; Michael Tripepi; Noah Talisa; Abdallah AlShafey; Joseph Smith; Stephen Londo; François Légaré; Enam Chowdhury; Gennady Shvets

doi:10.1038/s41467-023-42263-w

Nanoscale reshaping of resonant dielectric microstructures by light-driven explosions

Nat Commun. 2023 Oct 21;14(1):6688. doi: 10.1038/s41467-023-42263-w.

Authors

Maxim R Shcherbakov^{1

2}, Giovanni Sartorello^{3

4}, Simin Zhang⁵, Joshua Bocanegra^{6

7}, Melissa Bosch^{3

8}, Michael Tripepi^{9

10}, Noah Talisa^{10

11}, Abdallah AlShafey¹⁰, Joseph Smith¹², Stephen Londo¹³, François Légaré¹³, Enam Chowdhury^{5

10

14}, Gennady Shvets³

Affiliations

¹ Department of Electrical Engineering and Computer Science, University of California, Irvine, CA, 92697, USA. maxim.shcherbakov@uci.edu.
² Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA, 92612, USA. maxim.shcherbakov@uci.edu.
³ School of Applied and Engineering Physics, Cornell University, Ithaca, NY, 14850, USA.
⁴ Cornell NanoScale Science and Technology Facility, Cornell University, Ithaca, NY, 14853, USA.
⁵ Department of Material Science and Engineering, The Ohio State University, Columbus, OH, 43210, USA.
⁶ Department of Electrical Engineering and Computer Science, University of California, Irvine, CA, 92697, USA.
⁷ Department of Physics, University of California, Irvine, CA, 92697, USA.
⁸ Department of Physics, Cornell University, Ithaca, NY, 14850, USA.
⁹ Physics Department, Hillsdale College, Hillsdale, MI, 49242, USA.
¹⁰ Department of Physics, The Ohio State University, Columbus, OH, 43210, USA.
¹¹ Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA.
¹² Physics Department, Marietta College, Marietta, OH, 45750, USA.
¹³ Advanced Laser Light Source (ALLS) at Centre Énergie Matériaux Télécommunications, Institut national de la recherche scientifique, Varennes, Québec, J3X 1P7, Canada.
¹⁴ Department of Electrical and Computer Engineering, The Ohio State University, Columbus, OH, 43210, USA.

Abstract

Femtosecond-laser-assisted material restructuring employs extreme optical intensities to localize the ablation regions. To overcome the minimum feature size limit set by the wave nature of photons, there is a need for new approaches to tailored material processing at the nanoscale. Here, we report the formation of deeply-subwavelength features in silicon, enabled by localized laser-induced phase explosions in prefabricated silicon resonators. Using short trains of mid-infrared laser pulses, we demonstrate the controllable formation of high aspect ratio (>10:1) nanotrenches as narrow as [Formula: see text]. The trench geometry is shown to be scalable with wavelength, and controlled by multiple parameters of the laser pulse train, such as the intensity and polarization of each laser pulse and their total number. Particle-in-cell simulations reveal localized heating of silicon beyond its boiling point and suggest its subsequent phase explosion on the nanoscale commensurate with the experimental data. The observed femtosecond-laser assisted nanostructuring of engineered microstructures (FLANEM) expands the nanofabrication toolbox and opens exciting opportunities for high-throughput optical methods of nanoscale structuring of solid materials.