Single-sweep laser writing of 3D-waveguide devices

Abstract

We report on a method to create multiple waveguides simultaneously in 3D in fused silica. A combination of adaptive beam shaping with femtosecond laser writing is used to write two waveguides with changing separation and depth. The method is based on a programmable phase modulator and a dynamic variation of the phase-pattern during the writing process. The depth difference can be dynamically varied by changing a chirp parameter of the applied phase grating pattern. It can be employed in various photonic devices such as couplers, splitters and interferometers. Here we demonstrate splitters with both outputs ending in different depth.

Ultrafast-laser-inscribed 3D integrated photonics: challenges and emerging applications

“…Using a computer-generated hologram, multiple foci can be positioned in three dimensions [92,93]. This enables the single-sweep writing of several waveguides [94][95][96][97] or the inscription of multiscan waveguides in a single pass [98].…”

Roadmap on ultrafast optics

“…This scanner can scan a large spot over a 300 mm field-of-view with a spot-scanning velocity of up to 100 m s −1 . Another potential route to decrease fabrication times is to use a spatial light modulator to create multiple reconfigurable spots and hence more efficiently use of the power available from the laser [30,31], but this will require high power handling technologies.…”

Multi-beam second-harmonic generation in beta barium borate with a spatial light modulator and application to internal structuring in poly(methyl methacrylate)

“…By using an SLM to dynamically correct wavefront aberrations at the air/dielectric interface during the writing process in fused silica, real-time parallel 3D generation of longitudinally written waveguide couplers was demonstrated by Mauclair et al [8]. Pospiech et al [9] used single sweep adaptive beam shaping and depth control through the use of a chirp parameter applied to the phase grating pattern to create simultaneous 3D highquality waveguides and Y-splitters. More recently, Jesacher and Booth [10] introduced a new hologram design process which reduces diffractive power of the CGHs while retaining a high degree of parallelism, reducing distortion due to focal spot chromatic aberration.…”