Reconfigurable laser-written integrated photonic circuits

Introduction.We present experimental results on evaluation of the fully reconfigurable universal multiport architecture on the femtosecond laser-written platform. Furthermore, we propose new class of integrated reconfigurable... [ view full abstract ]

Introduction.

We present experimental results on evaluation of the fully reconfigurable universal multiport architecture on the femtosecond laser-written platform. Furthermore, we propose new class of integrated reconfigurable devices comprised of multiple waveguide lattices and a pattern of the thermooptical phaseshifters and investigate the reconfigurability features of such devices.

Methods.

We demonstrate a 4-by-4 multiport thermooptically tunable interferometer fully fabricated using the femtosecond laser writing technology. Currently lithography is the technological standard for fabricating reconfigurable photonic circuits. However, femtosecond laser writing provides the capability of very fast and cheap prototyping of both passive and active integrated photonic chips directly in the optical lab. We use the universal multiport interferometer design to achieve full reconfigurability of the device.

Results.

In this work we have elaborated the process of fabricating reconfigurable integrated photonic devices with tens of on chip resistive heaters. The fabricated device performs at a switching time of 10 ms setting a record for tunable femtosecond laser written devices. We present a thorough analysis of reconfigurability using an adaptive tuning strategy and provide an accurate account of the imperfections of reconfigurable devices fabricated with the femtosecond laser writing technology and possible approaches to overcome the reported issues. The work on 4-by-4 multiport thermooptically tunable interferometer could be found on this link:

https://arxiv.org/abs/1805.05323

The schematic of the tunable waveguide lattice device is presented in Fig. 1. The tunable waveguide lattices may serve as a special tool for experiments which don’t require full reconfigurability. We provide numerical results on the capabilities of such architecture and define classes of transformations which can be realized with high fidelity. The interest to such type of devices is dictated by novel multiphoton effects recently discovered in [1-2].

Discussion.

We believe that our work provides new and valuable tools for the integrated photonics community making the benefits of the reconfigurable integrated photonic devices available to a broader range of research groups.

References:

• A.J. Mensen, et al. Phys. Rev. Lett. 118, 153603 (2017)
• V.S. Shchesnovich and M.E.O. Bezerra, arXiv:1707.03893v2 (2018).