Multi-frequency laser monolithically integrating InGaAsP gain elements with amorphous silicon AWG

Abstract

We demonstrate a photonic integrated circuit using a novel monolithic integration platform combining InGaAsP gain elements and index matched amorphous silicon waveguide devices. The AWG based multi-frequency laser emits eight 100-GHz-spaced wavelengths near 1550 nm.OCIS codes: (250.5300) Photonic integrated circuits 1. Introduction Integration of photonic circuits is required to satisfy growing bandwidth demands in cost sensitive communication networks at affordable cost. Monolithic photonic circuits containing both active and passive components have been demonstrated using various integration techniques. Typically, the materials used for active as well as passive components in monolithic systems are InP and lattice matched epitaxially grown semiconductor compounds InGaAsP, GaInAlAs [1][2][3][4][5]. Most integrated devices require very low reflections and low loss at active-passive transitions. This makes materials that are popular for passive optical components such as SiO2/SiN/SiON and polymers less attractive for monolithic integration due to refractive indices much lower than those of the III/V compounds. Amorphous silicon alloys, transparent at telecommunication wavelengths (1310, 1550 nm), can be made with refractive indices matching those of III/V semiconductors but do not require lattice matched epitaxy. Optical waveguides made of amorphous silicon alloys deposited on silicon substrates have been explored in [6][7][8]. Low temperature PECVD deposition of amorphous silicon alloys makes this material system compatible with III/V components and substrates. In this paper we demonstrate the first monolithically integrated device combining amorphous silicon and III/V components. We have designed and fabricated a multi-frequency laser, which consists of InGaAsP/InP gain elements, and amorphous silicon waveguides, an amorphous silicon arrayed waveguide grating (AWG) and an amorphous silicon multimode interference (MMI) splitter monolithically integrated on an InP substrate.

Cost-effective telecom/datacom semiconductor lasers

“…Similar to the above mentioned tunable lasers, the monolithically integrated devices like laser integrated with optical amplifier or other devices, such as modulator, mode converter, beam splitter, optical isolator, arrayed wave guide (AWG) and so on [66][67][68][69][70][71] , bring many functions in a single monolithically integrated device which greatly reduces the size and cost of the systems or subsystems in optical telecom and datacom applications. Proc.…”

Amorphous silicon waveguide components for monolithic integration with InGaAsP gain sections

“…Amorphous silicon and amorphous silicon alloys such as amorphous silicon nitride or amorphous silicon carbide have received little attention for use as optical waveguides 1,2 or for application in integrated optics 3 .…”