Writing optical waveguides in fused silica using 1 kHz femtosecond infrared pulses

Abstract

We have investigated the writing of waveguides in bulk pure fused silica glass with femtosecond Ti:Sapphire laser at 1 kHz repetition rate. The photoinduced tracks were characterized in terms of writing geometry (parallel and perpendicular), pulse duration (45 fs, 140 fs, and 200 fs), pulse energy (1–10 μJ), and translation speed (5–150 μm/s) of the sample. Under specific writing conditions, uniform buried waveguides with circular cross section, core diameter of 3–4 μm, and refractive-index change as large as 5×10−3 between core and cladding were achieved.

Micromachining soda-lime glass by femtosecond laser pulses

“…Figure 1 shows the schematic of the longitudinally written laser lines (detail in Ref. [18]). The sample was moved parallel to the laser beam at a constant speed of 10 µm/s through the glass slab.…”

Fabrication of buried waveguides in planar silica films using a direct CW laser writing technique

“…Of these techniques, UV irradiation [1,2] or femto-second lasers [3][4][5] have been used to induce an increase in the refractive index of the exposed region in silica and in doped silica planar films. Experimental parameters such as exposure time, optical power and focused beam size have a profound influence on the change in the refractive index.…”

Understanding the beam self-cleaning behavior of ultrashort laser pulse filamentation

“…Filamentation involves the interplay of many physical processes, namely self-focusing, plasma generation, self-phase modulation (SPM), group velocity dispersion, self-steepenning [6,7] , third harmonic generation (THG) [8] , etc. Despite the obvious research interest from the point of view of the fundamental physics, the filamentation phenomenon starts to show its impact on a wide range of applications, from atmospheric remote sensing [9 -11] , to lightening control [12 -15] , to writing waveguides in glasses [16][17][18] , to creating few cycle pulses [19,20] and so on. Thus it is inevitable that filamentation will attract more and more researchers from various relevant fields.…”