Correlated photon pair generation in AlGaAs nanowaveguides via spontaneous four-wave mixing.

Pisek Kultavewuti,J Stewart Aitchison,Eric Y Zhu,Marc Sorel,Li Qian,Vincenzo Pusino

doi:10.1364/oe.24.003365

Abstract

We demonstrate a source of correlated photon pairs which will have applications in future integrated quantum photonic circuits. The source utilizes spontaneous four-wave mixing (SFWM) in a dispersion-engineered nanowaveguide made of AlGaAs, which has merits of negligible two-photon absorption and low spontaneous Raman scattering (SpRS). We observe a coincidence-to-accidental (CAR) ratio up to 177, mainly limited by propagation losses. Experimental results agree well with theoretical predictions of the SFWM photon pair generation and the SpRS noise photon generation. We also study the effects from the SpRS, propagation losses, and waveguide lengths on the quality of our source.

Highlights

Correlated photon pairs have potential applications in future communications and information processing systems
In the actual spontaneous four-wave mixing (SFWM) experiment, we only focus on co-polarized transverse electric (TE)-mode SFWM where both the signal and the idler photons are created in the TE modes of the waveguide
Background noise measurement suggests that the spontaneous Raman scattering (SpRS) photon noise from fiber components is negligible in our setup compared to the SpRS noise generated from the AlGaAs waveguide

Summary

Introduction

Correlated photon pairs have potential applications in future communications and information processing systems. Integrated sources of correlated photon pairs in AlGaAs have been rigoursly studied with device structures including superlattice waveguides [7, 8] and Braggreflection waveguides [4, 9, 10]. These structures rely on the second-order susceptibility. Control in AlGaAs waveguide dispersion allows a wide-band pump photon acceptance and a broad correlated photon pair generation bandwidth. These characteristics, in conjunction with on-chip integrateability, makes AlGaAs a very attractive platform to realize a quantum photonic circuit. The interplay between SFWM-generated photon pairs, SpRS noise, propagation loss, and waveguide length is studied

Theoretical background and device design

Fabrication and classical characterization

SFWM experimentation and results

Discussion

Conclusion