Polymer wavelength channel selector composed of electrooptic polymer switch array and two polymer arrayed waveguide gratings

An all-polymer wavelength channel selector is proposed and fabricated using chip-to-chip bonding of 16-channel electrooptic polymer switch array between two polymer arrayed waveguide gratings for the first time to our knowledge. A low power penalty of 0.1 dB at 10 Gb/s shows its potential as a wavelength channel selector for a packet switching system. Further efforts, however, should be paid to improve upon the large insertion loss of about 28 dB and bias phase drift problem for the proposed polymer channel selector to be a practical device.

I. Introduction

A WAVELENGTH channel selector capable of separating one wavelength channel from lots of multiplexed wavelength channels is a key functional device for network nodes in wavelength-division-multiplexed (WDM) optical networks. Most channel selectors have been realized by using either hybrid or monolithic integration of semiconductor optical amplifier (SOA) switch arrays between a pair of arrayed waveguide grating (AWG) demultiplexers and multiplexers [1]–[3]. Fig. 1. (a) Photograph of the fully packaged all-polymer wavelength channel selector and (b) its schematic diagram. The SOA-based wavelength channel selectors have shown good performance as well as advantages such as loss free operation and compact size. However, the SOA-based channel selectors are expensive because of a very low yield in production line caused by many delicate fabrication processes. It is also well known that the amplified spontaneous emission (ASE) from the SOAs causes significant degradation of optical WDM signal transmission characteristics. In this letter, an all-polymer-based wavelength channel selector is proposed. Electrooptic (EO) polymer switches and polymer AWGs are cost effective against corresponding semiconductor devices due to relatively simple fabrication processes and low material cost, and suitable for wavelength channel selector due to the capability for large scale integration [4]. The proposed all-polymer wavelength channel selector is fabricated, for the first time to the best of our knowledge, by using chip-to-chip bonding technology of the polymer devices in order to investigate its potential for practical devices.