Optical Tomography of Laser-Fabricated Waveguides

Authors: Shalmalee Deshpande, Nicole Batista, Devi Sapkota, Jack Agnes, Cameron Lapadula, Yuxuan Zhang, Bonggu Shim

Field of Study: Science, Technology, Engineering, and/or Math

Program Affiliation: Scalable Asymmetric Lifecycle Engagement (SCALE)

Faculty Mentors: Bonggu Shim

Easel: 40

Timeslot: Midday

Abstract: This study employs optical tomography to investigate the 3-D index profiles of femtosecond laser-fabricated waveguides. By immersing the waveguides in an index-matching fluid, this research reconstructs their internal structure and analyzes their 3-D index profiles using interferometer-based optical tomography. To establish a benchmark, this method is first applied to a commercial fiber optic cable, providing a reference for evaluating the laser-written waveguides. In particular, the machine-learning technique is utilized for limited-angle tomography to visualize the 3-D index profiles inside glass. This method has the potential of 3-D visualization of waveguides and structures for system-on-chip applications, where precise control in fabrication and component visualization is critical for efficient optical communication and processing.