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MANUFACTURING with short pulse lasers
FEMTOSECOND LASER STRUCTURING OF GLASSES
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Matthieu BELLEC 1, *, Maxime CAVILLON 2, Matthieu LANCRY 2, Yannick PETIT 3, Lionel CANIONI 3
1
Institut de Physique de Nice( INPHYNI), Université Côte d’ Azur, CNRS, Nice, France
2
Institut de Chimie Moléculaire et des Matériaux d’ Orsay( ICMMO), Université Paris-Saclay, CNRS, 91400 Orsay, France
3
Institut de Chimie de la Matière Condensée de Bordeaux( ICMCB), Université de Bordeaux, CNRS, INP Bordeaux, 87 Avenue du Dr Schweitzer, F-33608 Pessac, France * matthieu. bellec @ univ-cotedazur. fr
https:// doi. org / 10.1051 / photon / 202613738
This is an Open Access article distributed under the terms of the Creative Commons Attribution License( https:// creativecommons. org / licenses / by / 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Femtosecond lasers enable precise 3D nano- and micro-structuring in glasses, transforming photonic devices fabrication. The process relies on highly nonlinear interactions between femtosecond laser pulses and transparent materials, resulting in localized modifications of optical properties. In this article, we explore the fundamental mechanisms of laser-glass interactions, highlight advanced architectures for photonic integrated circuits, and discuss ongoing research aimed at expanding the range of achievable optical functionalities through innovative laser processing techniques and novel glass compositions.
Laser material processing has revolutionized modern manufacturing and materials science, offering precision and versatility across a vast array of applications. From cutting and polishing to surface texturing and bulk structuring, lasers, spanning continuous-wave and pulsed regimes, and wavelengths from ultraviolet to mid-infrared, enable the tailored modification of diverse materials, including metals, crystals, polymers, and glasses. Among these, femtosecond lasers have emerged as a tool of choice, particularly for the three-dimensional( 3D) nano- and micro-structuring of glasses. This capability is crucial for photonics, where femtosecond laser writing facilitates the fabrication of advanced photonic integrated circuits( PICs) for quantum optics, ultracompact optical devices, archival data storage solutions with unprecedented longevity and density, and even fiber Bragg gratings( FBGs) when optical fibers are considered.
This article explores the fundamental physicochemical mechanisms underpinning femtosecond laser-induced changes in glasses, with a focus on the 3D-localized controlled modifications of optical properties. We then examine how these fundamental building blocks enable the realization of advanced photonic components and systems, bridging the gap between material science and functional devices. Finally, we highlight ongoing research efforts that aim at developing novel optical functionalities through innovative processing approaches and novel glass compositions.
FROM LASER-GLASS INTERACTION TO OPTICAL PROPERTIES The interaction of femtosecond laser pulses with transparent materials, such as glasses, is governed by highly nonlinear processes occurring at a( sub) micrometer scale at the vicinity of the focal volume [ 1 ], as illustrated in Figure 1. In the single-pulse regime, nonlinear absorption, through quasi-instantaneous(~ fs) multiphoton absorption and tunnel ionization followed by cascade effects like avalanche ionization(~ 100 fs), generates
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