Tens of GHz Tantalum pentoxide-based micro-ring all-optical modulator for Si photonics
Journal
Annalen der Physik
Journal Volume
529
Journal Issue
3
Date Issued
2017
Author(s)
Wu, C.-L.
Hsieh, C.-H.
Lin, G.-R.
Chi, W.-C.
Chiu, Y.-J.
Lin, Y.-Y.
Hung, Y.-J.
Shih, M.-H.
Chu, A.-K.
Lee, C.-K.
Abstract
A tantalum pentoxide‐based (Ta 2 O 5 ‐based) micro‐ring all‐optical modulator was fabricated. The refractive index inside the micro‐ring cavity was modified using the Kerr effect by injecting a pumped pulse. The transmittance of the ring resonator was controlled to achieve all‐optical modulation at the wavelength of the injected probe. When 12 GHz pulses with a peak power of 1.2 W were coupled in the ring cavity, the transmission spectrum of the Ta 2 O 5 resonator was red‐shifted by 0.04 nm because of the Kerr effect. The relationship between the modulation depth and gap of the Ta 2 O 5 directional coupler is discussed. An optimized gap of 1100 nm was obtained, and a maximum buildup factor of 11.7 with 84% modulation depth was achieved. The nonlinear refractive index of Ta 2 O 5 at 1.55 μm was estimated as 3.4 × 10 −14 cm 2 /W based on the Kerr effect, which is almost an order of magnitude higher than that of Si 3 N 4 . All results indicate that Ta 2 O 5 has potential for use in nonlinear waveguide applications with modulation speeds as high as tens of GHz. image
SDGs
Type
journal article