Opticalparametric amplifiers in SiN waveguides coated with graphene
oxide thin films
Abstract
Optical parametric amplification (OPA) represents a powerful solution to
achieve broadband amplification in wavelength ranges beyond the scope of
conventional gain media, for generating high-power optical pulses,
optical microcombs, entangled photon pairs and a wide range of other
applications. Here, we demonstrate optical parametric amplifiers based
on silicon nitride (Si3N4) waveguides integrated with two-dimensional
(2D) layered graphene oxide (GO) films. We achieve precise control over
the thickness, length, and position of the GO films using a
transfer-free, layer-by-layer coating method combined with accurate
window opening in the chip cladding using photolithography. Detailed OPA
measurements with a pulsed pump for the fabricated devices with
different GO film thicknesses and lengths show a maximum parametric gain
of ~24.0 dB, representing a ~12.2 dB
improvement relative to the device without GO. We perform a theoretical
analysis of the device performance, achieving good agreement with
experiment and showing that there is substantial room for further
improvement. This work demonstrates a new way of achieving high photonic
integrated OPA performance by incorporating 2D materials.