High harmonic generation (HHG) in graphene quantum dots of armchair edge by strong coherent electromagnetic radiation taking into account collective electron-electron scattering as well in such nanosystems is considered. The microscopic quantum theory describing the plane quantum dot-laser field nonlinear interaction within the dynamic Hartree–Fock approximation is developed. The many-body Coulomb interaction is considered in the extended Hubbard approximation. The obtained results indicate the significance of the nanostructure lateral size, shape, and bandgap width in HHG process that allows to increase in the quantum yield of high-order harmonics and the cutoff photon energy.

An on-package optical interconnect design is proposed for the first time, with silicon photonics in conjunction with the polymer-on-glass interposer technology to enable heterogeneous integration. Glass substrates are used for low-cost, high reliability packaging while silicon photonics allows for high-speed modulation and wavelength division multiplexing within a small footprint. By combining silicon-photonic and benzo-cyclobutene-on-glass interposer technologies, we propose a scalable on-package photonic interconnect that can provide data rates >224  Gb  /  s for medium-reach links. Our proposed interconnect considers microring modulators and high-speed detectors available in photonic-foundry processes. We present the power-budget analysis to identify the key limiting parameters toward achieving an energy consumption of   <  1  pJ  /  bit.

We propose and demonstrate an all-fiber sensor for simultaneous measurement of strain and temperature that is based on a no-core fiber (NCF) and pure-silica-core fiber (PSCF). Two segments of NCF used as a beam splitter and combiner were embedded on the two ends of the PSCF, which constitutes a Mach–Zehnder interferometer (MZI) susceptible to the strain and temperature. With the change of strain and temperature, the dip wavelengths of transmission spectrum shifted, and simultaneous measurement of strain and temperature was realized by means of a sensitivity coefficient matrix. The experimental results showed that the sensitivity of strain was −0.6 and − 0.9 pm / με in the range from 0 to 1000 με, and the sensitivity of temperature ranging from 20°C to 80°C was 16.9 pm/°C and 11.7 pm/°C, respectively. Furthermore, the fiber sensor processed the advantages of easy-fabrication, compactness, low cost, and all-fiber configuration, and it has potential applications in blade load and damage monitoring in the field of wind power generation.

A numerical simulation of a metamaterial broadband absorber is performed using the finite-difference time-domain method. The absorber adopts a four-layer structure with titanium dioxide (TiO₂) rectangular pairs, a bismuth (Bi) layer, a silicon dioxide (SiO₂) layer, and a titanium nitride (TiN) layer from top to bottom, respectively, and the TiO₂ rectangular pairs are periodically and symmetrically arranged in a rectangular array. The optimization results show that the average absorption of the designed absorber is 97.6% in the wavelength range of 500 to 3500 nm and the average absorption can reach 99% in the wavelength range of 811 to 3162 nm (2351 nm). The coupling of local surface plasmon resonance and propagating plasmon resonance and the good absorption and broadband absorption properties exhibited by metallic Bi were further found by analyzing the distribution of electromagnetic fields. The designed absorber has polarization and temperature-insensitive properties and a simple structure and is easily fabricated.

The deposition of silica nanoparticles on Escherichia coli bacteria was investigated. The noncovalent interaction between the silanized surfaces and polar components of the biomembrane resulted in a nanobiostructure. This hybrid architecture showed stable conformation characteristics evaluated with different microscopy techniques, such as bright field confocal microscopy and transmission electron microscopy (TEM). Nanobioarchitectures were detected within colloidal dispersions and in the absence of aqueous media. Nanobiointeractions were related to strong polar and hydrogen bridges’ noncovalent interactions. Thus, well-constituted and defined nanobiostructures were observed by bright field confocal microscopy and TEM after their preparation in optimal conditions. However, to evaluate their stability and internanobiostructure interactions, size distributions within variable periods were determined. Variable nanobioaggregate sizes were recorded according to nanoparticles and bacteria concentrations. From single nanolabeled E. coli with well dispersible properties, low bacteria concentrations were observed. In intermediate and high concentrations, different distributions of nanobiostructures were observed in different periods. It was observed that the incorporation of silica nanoparticles into E. coli increased their dispersibility; however, their modified E. Coli membranes with silanized nanosurfaces augmented their internanobiostructure interactions through time. Here, we discuss the dynamics and nanobio-optics properties of E. coli. Their nanobiostructures could not be considered to be static systems; their interactions are regarded as important factors for dispersibility, stability, and effects against additional chemical agents such as antibiotics.

A mode-locked thulium–holmium fiber laser operating in the 2.0-μm wavelength region was demonstrated using a MAX phase titanium aluminum nitride (Ti₂AlN)-based saturable absorber (SA). The Ti₂AlN was prepared in the solution form and then drop-casted onto a homemade arc-shaped fiber, which served as the SA device. The mode-locked pulses were generated when the pump power was at 119 mW, and the pulses were sustained up to a pump power of 249 mW. The mode-locked fiber laser using the Ti₂AlN-based SA operated with a center wavelength of 1900.6 nm, having a repetition rate and a pulse width of 12.14 MHz and 1.61 ps, respectively. At the maximum pump power, the mode-locked pulses had maximum pulse energy of 0.35 nJ and peak power of 216 W. We propose the generation of short pulses using a MAX phase-based SA that could be useful for various applications in the eye-safe region.

Data are transmitted at a higher rate over long and short distances to fulfill the global requirement using all-optical (AO) technology. The reliability or accuracy of data transmission is also a key factor along with the higher data rate to achieve today’s desire perfectly. The cyclic redundancy check (CRC) code is a powerful, robust, and widely used error detecting code for data communication system and storage devices to find any unintentional changes during transmission. A (7, 4) CRC encoder has been analyzed numerically using AO silicon microring resonator (MRR) at a high-operational speed of 260 Gbps. CRC encoder is designed using MRR-based XOR gates and D flip flops. The proposed CRC encoder circuit is validated through MATLAB simulation. The optimization of essential parameters is accomplished through simulation against various metrics. These parameters could be utilized for practical execution of this design.

A surface plasmon polaritons (SPPs) waveguide structure composed of a metal–insulator–metal waveguide with a baffle, a special square cavity (SSC), and a ring cavity (RC), is proposed to realize independent tuning in triple Fano resonances. Using the finite element method, the magnetic field distributions and optical transmission spectra of the structure are analyzed in detail. The simulation results show that the structure achieves triple Fano resonances originated from two different mechanics. One of Fano resonances occurs in the RC, and the others occur in SSC. By regulating the structure parameters of the SSC and RC, these Fano resonances can be well tuning, and independently tuning is realized in multiple Fano resonances, which provides flexibility for the structure to be applied to optical devices. In addition, the structure exhibits great performances in refractive index sensing and biosensing. The maximum sensitivity of refractive index sensing achieves 2350 nm/RIU, and there is a good linear relationship between resonance wavelength and refractive index. Due to great sensitivity and independent tunability, the SPPs waveguide structure may be potentially used in micronano-optical devices, especially in optical on-chip sensor.

To achieve a flexible and reconfigurable topological edge state waveguide, we construct a valley photonic crystal (VPC) with liquid crystal filled rods. The permittivity of the two inequivalent rods in a unit is determined through the external voltage, which leads to a VPC with different valley topological phases. The external voltage is controlled by the codes of “0” and “1” on a control panel. Through programming the codes, arbitrary paths of topological edge states are achieved. The results were demonstrated by field propagation simulations.