Photonic Devices

Optical phased arrays can steer a beam without mechanical rotation, thus achieving a very rapid scanning rate. The core element of an optical phased array is the pixel (unit cell) and its ability to control the phase and amplitude of the emitted/scattered light. We discuss the role of nanophotonics in achieving pixels that are small […]

Ongoing progress in photonic integrated circuits necessitates the integration of semiconductor ring lasers (SRLs) with high performance and predictable behavior, which can be achieved when the symmetry of the SRL, which supports both clockwise and counterclockwise beam propagation, is unbalanced through loss mechanisms inside the resonator. In this work, numerical simulations were carried out on […]

In this work we present a generalized transfer matrix method to study the effect of the photon recycling on the performance of solar cells. Photon recycling increases the charge carrier concentration in solar cells, resulting in an increase of the open circuit voltage (Voc). The model is based on the transfer matrix method (TMM), taking […]

Due to the large computational resources required, with CPU times of the order of several days, full-wave optical simulators can be hardly exploited for the modeling and optimization of plasmonic organic hybrid electro/optic modulators. With the aim to drastically reduce such complexity, in this work we present a divide-et-impera strategy reducing the number of FDTD […]

A broadband integrated notch filter, using the silicon nitride (Si3N4) platform, is presented. It achieves an extinction ratio (ER) of 60 dB and a full width at half maximum (FWHM) of 10 nm at the central wavelength (CW) 785 nm. The main filter components are Bragg gratings (BGs). For separating the occurring reflections from the […]

We proposed an integrated-optical biosensor configuration that operates at a wavelength of 0.63 μm based on the evanescent-wave and lateral two-mode power coupling of Si3N4 rib-optical waveguides formed on a Si/SiO2/Si3N4/SiO2 multilayer thin films. The coupling between the two propagating modes in the sensing region produces a periodically repeated optical power exchange along the propagation. […]

Intrapulse coherence is an important performance metric for applications of supercontinua, including precision frequency metrology and attosecond science. These applications require a stable carrier-envelope phase, which is usually measured by f–2f interferometry. Here, the potential for superior intrapulse coherence with 100 and 400-fs input pulses is studied, exploiting different dispersion profiles. The simulation results in […]

Phase-modulated waveguide gratings are promising reflective optical elements for widely tunable laser applications. We present an analysis on their comb-like reflectivity response and address the impact of phase-shifts on the number of large reflection peaks, their envelope and on the effective grating coefficient. Utilizing a robust phase-modulation approach, this paper shows a quasi-stochastic numerical optimization […]

In this preliminary investigation, a statistical approach is proposed to analyze the nonlinear harmonic distortions introduced by Mach-Zehnder modulators (MZMs) in response to arbitrarily random radio frequency (RF) excitation signals. The proposed analysis is based on a simple and accurate reformulation of the MZM transfer characteristics using the Taylor series expansion and the Binomial Theorem. […]

An asymmetric dual core photonic crystal fiber (ADC-PCF) tunable polarization splitter is reported and analyzed. The left core of the DC-PCF is infiltrated with nematic liquid crystal (NLC) material to control the wavelength at which coupling occurs between the dual cores of the proposed structure. Moreover, the suggested design can be tuned to split out […]