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We investigate the dynamics of Na clusters embedded in Ar matrices. We use a hierarchical approach, accounting microscopically for the cluster's degrees of freedom and more coarsely for the matrix. The dynamical polarizability of the Ar atoms and the strong Pauli-repulsion exerted by the Ar-electrons are taken into account. We discuss the impact of the matrix on the cluster gross properties and on its optical response. We then consider a realistic case of irradiation by a moderately intense laser and discuss the impact of the matrix on the hindrance of the explosion, as well as a possible pump probe scenario for analyzing dynamical responses.

The graphite nanoparticles (GNPs) were prepared on the surface of monocrystalline Si by laser irradiation under different laser energy densities (3.3–8.33 kJ/cm²). The effects of laser energy density on structure and surface morphology were systematically investigated. The results show that the morphology of GNPs remained polycrystalline structure under laser irradiation with an energy density of 2.22 kJ/cm². When the laser energy density was 2.78 kJ/cm², the GNPs can induce the preset GNPs to transform into amorphous graphite nanofibers. The GNPs under the laser density of 3.33 kJ/cm² showed a more amorphous structure. With the further increase of the laser energy density to 5.55 kJ/cm², the main phase composition turned to SiC and Si.

Stimulated emission has been observed from oxide structure of silicon when optically excited by 514 nm laser. The twin peaks in the region from 690 nm to 700 nm are dominated by stimulated emission which can be demonstrated by its threshold behavior and transition in linear evolution. The oxide structure was fabricated by laser irradiation and annealing treatment on silicon. A model for explaining the stimulated emission has been proposed in which the trap states of the interface between oxide of silicon and porous nanocrystal play an important role.

Laser-induced thermal–mechanical damage characteristics of window materials are the focus problems in laser weapon and anti-radiation reinforcement technology. Thermal–mechanical effects and damage characteristics are investigated for cleartran multispectral zinc sulfide (ZnS) thin film window materials irradiated by continuous laser using three-dimensional (3D) thermal–mechanical model. Some temperature-dependent parameters are introduced into the model. The temporal-spatial distributions of temperature and thermal stress are exhibited. The damage mechanism is analyzed. The influences of temperature effect of material parameters and laser intensity on the development of thermal stress and the damage characteristics are examined. The results show, the von Mises equivalent stress along the thickness direction is fluctuant, which originates from the transformation of principal stresses from compressive stress to tensile stress with the increase of depth from irradiated surface. The damage originates from the thermal stress but not the melting. The thermal stress is increased and the damage is accelerated by introducing the temperature effect of parameters or the increasing laser intensity.

Aluminum and its alloys are widely used in our daily life because of their desirable physical properties. Improving the quality of Al-alloys surface layers is required for industrial applications. Nd: YAG pulsed Nanosecond Laser was used in irradiating aluminum 1100 alloy to study the surface morphology and hardness properties. Scanning Electron Microscope (SEM) images reveal the presence of small holes with different diameters that are produced by the irradiation of Aluminum alloy surfaces with different laser power densities. The diameters of the produced holes are decreased gradually by increasing the laser power density. Minimum diameter of about 1.84$\mu$m is obtained after irradiating the aluminum surface with 1256.04MW/cm² at which semi-periodic holes-like pattern were produced. An increase in the Vickers microhardness values was obtained until the maximum value of 28 HV was reached at laser power density of 750.16MW/cm². After reaching the maximum value, a fast decrease in the microhardness values was observed. Such changes in microhardness values maybe attributed to the lattice disorder and the change in the defect density produced by laser irradiation.

We present a controlling technique of microporous structure by laser irradiation during self-organization process. Polymer solution was dropped on the substrate at high humid condition and the honeycomb structure of regularly aligned pores on the film was fabricated by attaching of water droplets on the solution surface. We demonstrated that it was possible to prevent forming of pores at the region of laser irradiation and flat surface was fabricated. The method of our study is microfabrication processing technique that combines the advantages of bottom up and top down techniques. This method is expected that it is applied to photonic crystals, biological cell culturing, surface science and electronics fields.

Modification by electronic excitation of semiconductor surfaces and carbon-related quasi-two-dimensional (2D) nanostructured materials, namely graphene, carbon nanotubes is reviewed. Defect creation in these materials takes place not by low-intensity photoirradiation, but by laser or electron irradiation. The defect creation processes are different from ordinary photochemical processes in molecules or in some solids like alkali halides, which can be modified by a localized exciton. It is pointed out that there are common features in defect creation by electronic excitation in semiconductor surfaces and carbon-related quasi-2D nanomaterials: the yield-intensity relation shows strong superlinearity for laser irradiation near the bandgap energies and linearity or weak superlinearity for higher energy electron or photon irradiation. These results are explained in terms of multi-hole localization, in which bonds are weakened more strongly and more energy is available upon recombination with trapped electrons in comparison with excitons. The multi-hole localized state is considered to be realized by the creation of dense excitons or by cascade excitation for laser irradiation and by multiple excitations or multiple exciton generation by single impacts for electron irradiation. The review includes also polymerization of C${}_{60}$ films by electronic excitation, which is induced by low-intensity photoirradiation as well as by laser or electron irradiation. The experimental observation that laser or electron irradiation polymerize C${}_{60}$ films differently from low-intensity photoirradiation is explained in terms of multi-hole localization similar to the defect formation mechanism. Although fragmentation of C${}_{60}$ is due to electronic excitation of the molecule, it is included in the review because its yield is strongly superlinear for laser irradiation near bandgap energies and weakly superlinear for high-energy electron or photon irradiation as for other cases.

Gold nanorods (AuNRs) have been considered as suitable materials for diverse biomedical applications in controlling cell behaviors. The nanoisland system with well-dispersed silica coated Au nanorods (Si-AuNRs) was used to demonstrate the enhanced cell growth of normal and cancer cells (MDA-MB-231 mammalian breast cancer cells) from the induced expressions of the heat shock proteins (HSPs). The over-expressions of HSP could help in protein folding in cell proliferations and growths of both the normal and cancer cells. In the current study, interesting mechanisms of cancer cell growth with Si-AuNRs than the conventional systems, such as incubator, would be presented. We believe that the growth of cancer cells in near infrared (NIR) region using Si-AuNRs induced the activities of HSPs, which could help the protein folding in cell growth and survival in comparison to the cells grown in the incubator only. The cell growth enhancing technology could be expanded in diverse applications in cell culture systems.

The ideal treatment modality for metastatic cancer would be a local treatment that can destroy primary tumors while inducing an effective systemic anti-tumor response. To this end, we developed laser immunotherapy, combining photothermal laser application with an immunoadjuvant for the treatment of metastatic cancer. Additionally, to enhance the selective photothermal effect, we integrated light-absorbing nanomaterials into this innovative treatment. Specifically, we developed an immunologically modified carbon nanotube combining single-walled carbon nanotubes (SWNTs) with the immunoadjuvant glycated chitosan (GC). To determine the effectiveness of laser irradiation, a series of experiments were performed using two different irradiation durations — 5 and 10 min. Rats were inoculated with DMBA-4 cancer cells, a metastatic cancer cell line. The treatment group of rats receiving laser irradiation for 10 min had a 50% long-term survival rate without residual primary or metastatic tumors. The treatment group of rats receiving laser irradiation for 5 min had no long-term survivors; all rats died with multiple metastases at several distant sites. Therefore, Laser+SWNT–GC treatment with 10 min of laser irradiation proved to be effective at reducing tumor size and inducing long-term anti-tumor immunity.

We investigate the dynamics of Na clusters embedded in Ar matrices. We use a hierarchical approach, accounting microscopically for the cluster's degrees of freedom and more coarsely for the matrix. The dynamical polarizability of the Ar atoms and the strong Pauli-repulsion exerted by the Ar-electrons are taken into account. We discuss the impact of the matrix on the cluster gross properties and on its optical response. We then consider a realistic case of irradiation by a moderately intense laser and discuss the impact of the matrix on the hindrance of the explosion, as well as a possible pump probe scenario for analyzing dynamical responses.