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Realizing single light solitons that are stable in high dimensions is a long-standing goal in research of nonlinear optical physics. Here, we address a scheme to generate stable two-dimensional solitons in a cold Rydberg atomic system with a parity-time (PT) symmetric moiré optical lattice. We uncover the formation, properties, and their dynamics of fundamental and two-pole gap solitons as well as vortical ones. The PT symmetry, lattice strength, and the degrees of local and nonlocal nonlinearity are tunable and can be used to control solitons. The stability regions of these solitons are evaluated in two numerical ways: linear-stability analysis and time evolutions with perturbations. Our results provide an insightful understanding of solitons physics in combined versatile platforms of PT-symmetric systems and Rydberg–Rydberg interaction in cold gases.

We propose a scheme to generate stable vector spatiotemporal solitons through a Rydberg electromagnetically induced transparency (Rydberg-EIT) system. Three-dimensional vector monopole and vortex solitons have been found under three nonlocal degrees. The numerical calculation and analytical solutions indicate that these solitons are generated with low energy and can stably propagate along the axes. The behavior of vector spatiotemporal solitons can be manipulated by the local and nonlocal nonlinearities. The results show a memory feature as these solitons can be stored and retrieved effectively by tuning the control field.

Lifting machinery is a key facility for the development of modern industry. It’s not noly an important support for the construction of major national projects but also one of the core competitiveness of my country’s equipment manufacturing industry. With the development of large-scale, high-parameterization and intelligentization of lifting appliances, technologies such as safety monitoring and health monitoring have been gradually applied to industrial fields such as ports and metallurgy. In order to further develop the data-driven health management technology and engineering application of cranes, on the basis of elaborating the health management needs of cranes, the current status and development trends at home and abroad, we explored and proposed a technical framework for health management of cranes, and analyzed the lifting Key technologies such as machinery safety monitoring, health monitoring, health status diagnosis, failure trend prediction, and predictive maintenance decisions. Finally combined with a 200t casting crane in a steel plant, carried out safety monitoring and data-driven diagnosis, prediction and system visualization management. The results show that: the hoisting machinery health management system can monitor and monitor in real time and carry out early warning and forecasting to avoid the occurrence of unexpected accidents; based on predictive maintenance decisions, it helps enterprises to reasonably arrange maintenance cycles and maintenance methods to reduce the maintenance cost of the enterprise; reduce hoisting machinery downtime Time to enhance the effective value of assets; and enhance the level of enterprise information management.

In this study, we analyze Cluster observations of whistler-mode chorus and hiss waves during the event of August 19-21, 2006. Chorus is present outside the plasmasphere and hiss occurs inside the plasmasphere. Using a recently constructed plasma boundary layer model, we perform a ray-tracing study on the propagation of chorus. Numerical results show that chorus can penetrate into the plasmasphere through the plasma boundary layer, evolving into hiss. The current data analysis and modeling provide a further observational support for the previous findings that chorus is the origin of plasmaspheric hiss.

Ray tracing study of electromagnetic ion cyclotron (EMIC) waves is conducted based on a realistic plasma density model. The simulation result shows that EMIC waves propagate away from the equatorial source region to higher latitudes basically along geomagnetic field lines, and are reflected at the region where their frequency matches the local bi-ion frequency. H+ band suffers H+-He+ bi-ion frequency reflection at lower latitudes, whereas He+ band suffers He+-O+ bi-ion frequency reflection at higher latitudes. Moreover, the concentration of heavy ions slightly affects the bi-ion frequencies and then slightly determines the reflection location of ray paths of EMIC waves. The current results present the first detailed study on the propagation characteristics of EMIC waves associated with bi-ion frequencies.

Based on homogeneous balance method, soliton solutions to a generalized nonlinear Schrodinger equation (NLSE) with varying coefficients have been gotten. Our results indicate that a new family of vortex or petal-like spatial solitons can be formed in the Kerr nonlinear media in the cylindrical symmetric geometry. It is shown by numerical simulation that these soliton profiles are stable.

The (1+1)-dimensional F-expansion technique and the homogeneous nonlinear balance principle have been generalized and applied for solving exact solutions to a general (3+1)-dimensional nonlinear Schrodinger equation (NLSE) with varying coefficients and a harmonica potential. We found that there exist two kinds of soliton solutions. The evolution features of exact solutions have been numerically studied. The (3+1)D soliton solutions may help us to understand the nonlinear wave propagation in the nonlinear media such as classical optical waves and the matter waves of the Bose–Einstein condensates.

The temporal and spatial dynamics of one weak probe laser pulse, propagating through a A-type atomic medium with two-folded levels under the resonant excitation of one microwave driving field and one strong control field, is investigated in this paper. By numerically solving coupled Bloch-Maxwell equations, it is found that, in the absence of the microwave driving field, the atomic medium is transparent to the probe pulse at line center, which propagates over sufficiently long distances. By contrast, when the microwave driving field is applied, the probe pulse at line center can be rapidly absorbed on propagation. This substantial reduction of probe transmittance caused by the microwave driving field may lead to potential applications in designing a new kind of optical switching.

We demonstrate the formation of ultraslow dark optical solitons with a four-level scheme in an asymmetric semiconductor double quantum well (SDQW) structure based on intersubband transitions by using only a low-intensity pulsed laser radiation. With appropriate conditions we show numerically that the dark optical soliton can travel with a ultraslow group velocity Vg/c ~ ? 10?3. Such a semiconductor system is much more practical than its atomic counterpart because of its flexible design and the controllable interference strength. This nonlinear optical process in the SDQW solid-state material may be used for the control technology of optical delay lines and optical buffers.

We investigate the formation of optical bistability (OB) in a crystal of molecular magnets contained in a unidirectional ring cavity. The crystal is subjected to one dc magnetic field and two (probe and coupling) ac resonant magnetic field. The results show that OB can be controlled efficiently by adjusting the intensity of the control field, the detuning of probe magnetic field and the cooperation parameter. Furthermore, within certain parameter range, the optical multistablity (OM) can also be observed in the crystal medium. This investigation can be used for designing new types of nonelectronic devices for realizing switching process.

We demonstrate three-dimensional (3D) vector solitary waves in the coupled (3 + 1)-D nonlinear Gross-Pitaevskii equations with variable nonlinearity coefficients. The analysis is carried out in spherical coordinates, providing novel localized solutions that depend on three modal numbers, l , m , and n . Using the similarity transformation (ST) method in 3D, vector solitary waves are built with the help of a combination of harmonic and trapping potentials, including multipole solutions and necklace rings. In general, the solutions found are stable for low values of the modal numbers; for values larger than 2, the solutions are found to be unstable. Variable nonlinearity allows the utilization of soliton management methods.

By combining the appropriate Ag metallic grids with a thin functional reduced graphene oxide (MGs/F-rGO) film, a suitable photoelectric flexible electrode of the polymer solar cells (PSCs) is obtained. The conductivity and transmission of the MGs/F-rGO composited films can be improved by HNO3 modified. The optimized sheet resistance and transmission of the flexible electrode achieve to 25 Ω −1 and 83% at 550 nm wavelength. Flexible PSCs with the MGs/F-rGO electrode show 5.63% power conversion efficiency. The photoelectric properties of the MGs/F-rGO film comparable with that of ITO substrates guarantee a high short current and an enhanced PCE of the solar cells. This method provides a feasible way for fabricating low-cost and flexible PSCs.

Based on the density functional theory, the influences of strain on structural, elastic, thermal and optical properties of CuGaTe2 are discussed in detail. It is found that the tensile strain on CuGaTe2 is beneficial to the decrease of lattice thermal conductivity by reducing the mean sound velocity and Debye temperature. Moreover, all strained and unstrained CuGaTe2 exhibit rather similar optical characters. But the tensile strain improves the ability to absorb sunlight in the visible range. These research findings can give hints for designing thermoelectric and photovoltaic devices.

We construct explicit spatiotemporal or light bullet (LB) solutions to the (3 + 1)-dimensional nonlinear Schrodinger equation (NLSE) with inhomogeneous diffraction/dispersion and nonlinearity in the presence of parity-time (PT) symmetric potential with competing nonlinearities. The solution is based on the similarity transformation, by which the initial inhomogeneous problem is reduced to the standard NLSE with constant coefficients but with redefined variables and potential. Transmission characteristics of LB solutions, such as the phase change, half width and chirp, are studied in the media with exponentially decreasing diffraction/dispersion and with periodic modulation. Our outcomes demonstrate that diffraction/dispersion and nonlinearity management can prolong the stability of LBs in a PT potential.

We construct exact self-similar soliton solutions of three-dimensional coupled Gross–Pitaevskii equations for two-species Bose–Einstein condensates (BECs) in a combined time-dependent harmonic-lattice potential. Based on these solutions, we investigate the control and manipulation of solitary waves for three kinds of BECs with changing diffraction and nonlinearity coefficients; the solutions include Ma breathers and Peregrine and Akhmediev soliton solutions. Our results indicate that matter waves readily propagate in this system. It is shown that diffraction and lattice potential factors play important roles in the beam evolution characteristics, such as the peak, the phase offset, the linear phase, and the chirp.

We investigate the existence of spatiotemporal necklace vortex solitons or light bullets in the complex Ginzburg-Landau equation with the modulated Kummer-Gauss (KG) external lattice potential and the spiraling phase of vorticities , and 2. We find localized vortex necklaces in a three-dimensional nonlinear medium, trapped by the KG external potential with different orders of vorticity. Stable and quasi-stable solitons form from input pulses with embedded vorticity. The stability is established by calculating growth rates of the perturbed eigenmodes. We establish that spatiotemporal necklace solitons may coexist in a large domain of the parameter space.

Photothermal ablation (PTA) is a promising avenue in the area of cancer therapeutics that destroys tumor cells through conversion of near-infrared (NIR) laser light to heat. Hollow gold nanospheres (HGNs) are one of the few materials that are capable of converting light to heat and have been previously used for photothermal ablation studies. Selective delivery of functional nanoparticles to the tumor site is considered as an effective therapeutic approach. In this paper, we demonstrated the anti-cancer potential of HGNs. HGNs were conjugated with monoclonal antibody (anti-TROP2) in order to target cervical cancer cells (HeLa) that contain abundant trophoblast cell surface antigen 2 (TROP2) on the cell surface. The efficient uptake and intracellular location of these functionalized HGNs were studied through application of inductively coupled plasma atomic emission spectroscopy (ICP-AES) and transmission electron microscopy (TEM). Cytotoxicity induced by PTA was measured using CCK-8 assay. HeLa cells incubated with naked HGNs (0.3-3 nmol L(-1)) within 48 h did not show obvious cytotoxicity. Under laser irradiation at suitable power, anti-TROP2 conjugated HGNs achieved significant tumor cell growth inhibition in comparison to the effects of non-specific PEGylated HGNs (P < 0.05). γH2AX assay results revealed higher occurrences of DNA-DSBs with anti-TROP2 conjugated HGNs plus laser radiation as compared to treatment with laser alone. Flow cytometry analysis showed that the amount of cell apoptosis was increased after laser irradiation with anti-TROP2 conjugated HGNs (P < 0.05). Anti-TROP2 conjugated HGNs resulted in down-regulation of Bcl-2 expression and up-regulation of Bax expression. Our study results confirmed that anti-TROP2 conjugated HGNs can selectively destroy cervical cancer cells through inducing its apoptosis and DNA damages. We propose that HGNs have the potentials to mediate targeted cancer treatment.

Textured silicon (Si) substrates decorated with regular microscale square pillar arrays of nearly the same side length, height, but different intervals are fabricated by inductively coupled plasma, and then silanized by self-assembly octadecyl-trichlorosilane (OTS) film. The systematic water contact angle (CA) measurements and micro/nanoscale hierarchical rough structure models are used to analyze the wetting behaviors of original and silanized textured Si substrates each as a function of pillar interval-to-width ratio. On the original textured Si substrate with hydrophilic pillars, the water droplet possesses a larger apparent CAs (> 90°) and contact angle hysteresis (CAH), induced by the hierarchical roughness of microscale pillar arrays and nanoscale pit-like roughness. However, the silanized textured substrate shows superhydrophobicity induced by the low free energy OTS overcoat and the hierarchical roughness of microscale pillar arrays, and nanoscale island-like roughness. The largest apparent CA on the superhydrophobic surface is 169.8°. In addition, the wetting transition of a gently deposited water droplet is observed on the original textured substrate with pillar interval-to-width ratio increasing. Furthermore, the wetting state transition is analyzed by thermodynamic approach with the consideration of the CAH effect. The results indicate that the wetting state changed from a Cassie state to a pseudo-Wenzel during the transition.

Using Hirota's bilinear method, we determine approximate analytical localized solutions of the (2 + 1)-dimensional nonlinear Schrodinger equation with variable diffraction and nonlinearity coefficients. Our results indicate that a new family of vortices can be formed in the Kerr nonlinear media in the cylindrical geometry. Variable diffraction and nonlinearity coefficients allow utilization of the soliton management method. We present solitary solutions for two types of distributed coefficients: trigonometric and exponential. It is demonstrated that the soliton profiles found are structurally stable, but slowly expanding with propagation.

The F-expansion technique and the homogeneous nonlinear balance principle have been applied for solving a general (1+1)-dimensional nonlinear Schrodinger equation (NLSE) with varying coefficients and a harmonic potential. A family of (1+1)D spatial solitons has been obtained. The evolution features of exact solutions have been investigated.