Ultra-Broadband Polymer 1 × 2 Thermo-Optic Mode Switch

Yang Gao,Songyue Liu,Xiaojian Fan,Xibin Wang,Xiaoqiang Sun,Yan Xu,Daming Zhang

doi:10.1109/jphot.2021.3097055

Abstract

Optical mode switch is a key device for reconfigurable mode-division-multiplexing (MDM) technique. Here, an ultra-broadband 1×2 mode switch based on cascaded Mach-Zehnder interferometer and asymmetric Y-branch is proposed. The input E 00 or E 10 mode will be converted to E 00 mode and switched between two output ports by changing the working state of electrode. When E 00 mode is launched, the measured insertion loss of fabricated switch is 3.3 dB (off-state)/3.4 dB (on-state), and corresponding crosstalk is -18.8 dB (off-state)/-16.1 dB (on-state) at 1550 nm, respectively. Due to the adoption of polymer with high thermo-optic coefficient as the waveguide material, the measured switching power is 10.3 mW. The captured far-field output mode patterns prove the wavelength independence of proposed mode switch within the range from 1500 to 1630 nm. This broadband operation mode switch has potentials in wavelength-division-multiplexing & MDM complex systems, as well as cost-effective low-end switching applications.

Highlights

T HE transmission capacity of optical communication systems based on single-mode fibers is approaching the nonlinear Shannon limit [1]–[2]
When the driving power increases to 10.3 mW, the input E00 mode outputs from Port O2, insertion loss (IL) and CT are measured to be 3.4 dB and −16.1 dB, respectively
We have designed and experimentally demonstrated an ultra-broadband polymer 1 × 2 mode switch based on cascaded Mach-Zehnder interferometer (MZI) and asymmetric Y-branch mode demultiplexer in this work

Summary

Introduction

T HE transmission capacity of optical communication systems based on single-mode fibers is approaching the nonlinear Shannon limit [1]–[2]. Over the past several decades, several multiplexing techniques, such as wavelengthdivision -multiplexing (WDM) [3]–[8], polarization-divisionmultiplexing (PDM) [9]–[13] and mode-division-multiplexing (MDM) [14]–[19], have been proposed to satisfy the everincreasing capacity demands of optical link. WDM that introduces multiple independent wavelength channels to carry different signals is one of the most widely used technologies. The transmission capacity of WDM method is becoming saturated due to the bandwidth limitation. Manuscript received May 25, 2021; revised July 7, 2021; accepted July 10, 2021. Date of publication July 14, 2021; date of current version August 25, 2021.

Methods

Results

Conclusion