相关论文: Electrically Tunable Optical Nonlinearities in Gra…
Nonlinear optics, especially frequency mixing, underpins modern optical technology and scientific exploration in quantum optics, materials and life sciences, and optical communications. Since nonlinear effects are weak, efficient frequency…
Graphene is a 2D material with appealing electronic and optoelectronic properties. It is a zero-bandgap material with valence and conduction bands meeting in a single point (Dirac point) in the momentum space. Its conductivity can be…
Various bandstructure engineering methods have been studied to improve the performance of graphitic transparent conductors; however none demonstrated an increase of optical transmittance in the visible range. Here we measure in situ optical…
We present theoretical and experimental evidence of high-gain far-detuned nonlinear frequency conversion, extending towards both the visible and the mid-infrared, in a few-mode graded-index silica fiber pumped at 1.064 $\mu$m, and more…
Optical harmonic generation occurs when high intensity light ($>10^{10}$W/m$^{2}$) interacts with a nonlinear material. Electrical control of the nonlinear optical response enables applications such as gate-tunable switches and frequency…
For optical communication, information is converted between optical and electrical signal domains at a high rate. The devices to achieve such a conversion are various types of electro-optical modulators and photodetectors. These two types…
Materials with massless Dirac fermions can possess exceptionally strong and widely tunable optical nonlinearities. Experiments on graphene monolayer have indeed found very large third-order nonlinear responses, but the reported variation of…
Graphene is conceivably the most nonlinear optoelectronic material. Its nonlinear optical coefficients in the terahertz (THz) frequency range surpass those of other materials by many orders of magnitude. This, in particular, allows one to…
In this paper we present a novel fabrication technique for silicon nitride (Si3N4) waveguides with a thickness of up to 900 nm, which are suitable for nonlinear optical applications. The fabrication method is based on etching trenches in…
The ability to tune the optical response of a material via electrostatic gating is crucial for optoelectronic applications, such as electro-optic modulators, saturable absorbers, optical limiters, photodetectors and transparent electrodes.…
Graphene placed in a magnetic field possesses an extremely high mid/far-infrared optical nonlinearity originating from its unusual band structure and selection rules for the optical transitions near the Dirac point. Here we study the linear…
Integrated waveguides exhibiting efficient second-order nonlinearities are crucial to obtain compact and low power optical signal processing devices. Silicon nitride (SiN) has shown second harmonic generation (SHG) capabilities in resonant…
We experimentally demonstrate enhanced self-phase modulation (SPM) in silicon nitride (Si3N4) waveguides integrated with 2D graphene oxide (GO) films. GO films are integrated onto Si3N4 waveguides using a solution-based, transfer-free…
Graphene has been considered as a promising material for opto-electronic devices, because of its tunable and wideband optical properties. In this work, we demonstrate electro-refractive phase modulation in graphene at wavelengths from 1530…
We present the design, simulation and optimization of a graphene-on-silicon nitride (GOSiN) integrated waveguide dual-mode electro-absorption modulator operating with a speed between 27-109 GHz and an energy consumption below 6 pJ/bit. This…
While the Dirac band structure of graphene has established it as a leading platform for ultrafast optoelectronics, its non-perturbative nonlinear response under intense excitation remains poorly understood. Here, we report ultrafast…
A non-perturbative model for graphene optical nonlinearity is developed for the study of ultrafast pulse propagation along a monolayer, as in the case of graphene-comprising nanophotonic integrated waveguides. This graphene `hot electron'…
An electro-absorption optical modulator concept based upon a dual-graphene layer is presented. The device consists of a silicon-on-insulator waveguide upon which two graphene layers reside, separated by a thin insulating region. The lower…
Tunable lasers emitting at a 2-3 $\mu$m wavelength range and compatible with photonic integration platforms are of great interest for sensing applications. To this end, combining GaSb-based semiconductor gain chips with Si$_3$N$_4$ photonic…
Graphene photonics has emerged as a promising platform for providing desirable optical functionality. However, graphene's monolayer-scale thickness fundamentally restricts the available light matter interaction, posing a critical design…