Graphene-based electro-optical modulators integrated into polymer waveguide with three dielectric materials proposals

Author(s)

Camacho, Wanderson A. ; Thoroh de Souza, Eunezio A. ; Saito, Lucia A. M. ; IEEE

• Document type: Journal article
• Source: 2018 SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE (SBFOTON IOPC); v. N/A, p. 4-pg., 2018-01-01.

Abstract

This work presents an analysis of electro-optical modulators integrated into polymer waveguides, which operates over electro-absorption effect through graphene. This study focus in three different dielectric materials for the capacitive structure in the device such as silicon nitride, Si3N4, hafnium oxide, HfO2 and boron nitride, hBN. By varying the thickness of the dielectric material, it was possible to improve the extinction ratio, modulation frequency and reduce the switching voltages requirements. By considering a bottom cladding, it was possible to increase the light interaction with the graphene and obtain higher modulation frequencies. In the case of the device with HfO2, it was possible to obtain the highest extinction rate of 0.117 dB/mu m with a dielectric thickness of 50 nm. For the model with the hBN thickness layer of 50 nm, the maximum operation frequency was 35 GHz, considering a device length of 27 mu m. The condition with the minimum voltage requirements was obtained with HfO2, which the value switching was between 2.5 and 5 V. Although the results with Si3N4 are not the best, it is a good option when the device project try to match all the design requirements. (AU)

• FAPESP's process: 12/50259-8 - Graphene: photonics and opto-electronics: UPM-NUS collaboration
• Grantee: Antonio Helio de Castro Neto
• Support Opportunities: Research Projects - SPEC Program
• FAPESP's process: 15/11779-4 - Plasmonic and nonlinear effects in graphene coupled to optical waveguides
• Grantee: Christiano José Santiago de Matos
• Support Opportunities: Research Projects - Thematic Grants