Two-dimensional laser-induced periodic surface structures (LIPSSs) with a deep-subwavelength periodicity (80 nm ≈ λ/10) were obtained for the first time on diamond surfaces. The unique surface nanotexturing is achieved by employing a technique that relies on irradiation with two temporally delayed and cross-polarized fs-laser pulses generated with a Michelson-like interferometer configuration. In this paper, we demonstrate that, if the delay between two consecutive pulses is ≤ 2 ps, the 2D periodicity of nanostructures can be tuned by controlling the number of pulses irradiating the surface.
In this work, published on the prestigious journal Nano Letters, a cross-polarized, temporally-delayed double pulse technique was employed for the fabrication of two-dimensional periodic surface structures on diamond surface in a single irradiation step. The fabricated 2D-LIPSSs induce a reflectance decrease of approximately 75% in the wavelength range from 200 to 1000 nm. Furthermore, absorptance value is enhanced in the range from 400 nm to 1000 nm. The latter is ascribed to the light trapping capability of the regular periodic nanostructures that induce both a cavity-like trapping and a significant increase of the absorbing effective surface, with a consequent enhancement of the active surface-to-volume ratio involved in the light-matter interaction.
The work is a collaboration between CNR-ISM, CNR-INO and Semilab Germany.
M. Mastellone, A. Bellucci, M. Girolami, V. Serpente, R. Polini, S. Orlando, A. Santagata, E. Sani, F. Hitzel, D.M. Trucchi, Deep-subwavelength 2D periodic surface nanostructures on diamond by double-pulse femtosecond laser irradiation, Nano Letters, vol. 21, pages: 4477−4483 (2021). DOI: https://doi.org/10.1021/acs.nanolett.1c01310
#diamond #laser #surface_texturing #LIPSSs #metasurface #optical properties #advanced materials