Graphene Oxide-Gallic Acid Nanodelivery System for Cancer Therapy

Despite the technological advancement in the biomedical science, cancer remains a life-threatening disease. In this study, we designed an anticancer nanodelivery system using graphene oxide (GO) as nanocarrier for an active anticancer agent gallic acid (GA). The successful formation nanocomposite (GOGA) was characterized using XRD, FTIR, HRTEM, Raman, and UV/Vis spectroscopy. The release study shows that the release of GA from the designed anticancer nanocomposite (GOGA) occurs in a sustained manner in phosphate-buffered saline (PBS) solution at pH 7.4. In in vitro biological studies, normal fibroblast (3T3) and liver cancer cells (HepG2) were treated with different concentrations of GO, GOGA, and GA for 72 h. The GOGA nanocomposite showed the inhibitory effect to cancer cell growth without affecting normal cell growth. The results of this research are highly encouraging to go further for in vivo studies

Curved optical solitons subject to transverse acceleration in reorientational soft matter

We demonstrate that optical spatial solitons with non-rectilinear trajectories can be made to propagate in a uniaxial dielectric with a transversely modulated orientation of the optic axis. Exploiting the reorientational nonlinearity of nematic liquid crystals and imposing a linear variation of the background alignment of the molecular director, we observe solitons whose trajectories have either a monotonic or a non-monotonic curvature in the observation plane of propagation, depending on either the synergistic or counteracting roles of wavefront distortion and birefringent walk-off, respectively. The observed effect is well modelled in the weakly nonlinear regime using momentum conservation of the self-collimated beams in the presence of the spatial nonlocality of the medium response. Since reorientational solitons can act as passive waveguides for other weak optical signals, these results introduce a wealth of possibilities for all-optical signal routing and light-induced photonic interconnects

Magnetic steering of beam confined random laser in liquid crystals

Using an external magnetic field, we demonstrate in-plane angular steering of a green pumped random laser in dye-doped nematic liquid crystals, where a near-infrared reorientational spatial soliton provides a smooth output profile with emission in a well-defined direction. By varying the orientation of the applied magnetic field, the soliton-guided random laser beam can be steered over an angle as large as 14 degrees, corresponding to a transverse displacement of 0.49 mm at the output facet of a 2 mm-long sample

Electro-optic steering of random laser emission in liquid crystals

Using an external low-frequency electric field applied to dye-doped nematic liquid crystals, we demonstrate that random lasing obtained by optical pumping can be steered in an angular direction by routing an all-optical waveguide able to collect the emitted light. By varying the applied voltage from 0 to 2 V, we reduce the walk-off and sweep the random laser guided beam over 7 degrees

Near-Infrared Switching of Light-Guided Random Laser

We report on all-optical modulation and switching of light-guided random laser emission in optically pumped dye-doped nematic liquid crystals, whereby a continuous-wave near-infrared beam at 1.064 micrometer, non-resonant with the medium and collinear with the pump source, forms a reorientational spatial soliton. Such soliton-assisted cavity-less laser exhibits a beam character with directional emission and smooth transverse profile and can be either switched-on or made more efficient by injecting a mW input beam. We achieve energy amplifications of laser emission in excess of 18 dB by injecting a 6 mW near-infrared beam

Soliton-assisted random lasing in liquid crystals

We demonstrate random lasing control exploiting optical gain and light self-localization in a reorientational medium. A spatial soliton in dye-doped nematic liquid crystals modulates stimulated emission of visible light, yielding random lasing with enhanced features

Magnetic on–off switching of a plasmonic laser

| openaire: EC/H2020/948260 /EU//PLAS-OLEDThe nanoscale mode volumes of surface plasmon polaritons have enabled plasmonic lasers and condensates with ultrafast operation1–4. Most plasmonic lasers are based on noble metals, rendering the optical mode structure inert to external fields. Here we demonstrate active magnetic-field control over lasing in a periodic array of Co/Pt multilayer nanodots immersed in an IR-140 dye solution. We exploit the magnetic nature of the nanoparticles combined with mode tailoring to control the lasing action. Under circularly polarized excitation, angle-resolved photoluminescence measurements reveal a transition between the lasing action and non-lasing emission as the nanodot magnetization is reversed. Our results introduce magnetization as a means of externally controlling plasmonic nanolasers, complementary to modulation by excitation5, gain medium6,7 or substrate8. Further, the results show how the effects of magnetization on light that are inherently weak can be observed in the lasing regime, inspiring studies of topological photonics9–11.Peer reviewe

Magnetic on-off switching of a plasmonic laser

The nanoscale mode volumes of surface plasmon polaritons have enabled plasmonic lasers and condensates with ultrafast operation(1-4). Most plasmonic lasers are based on noble metals, rendering the optical mode structure inert to external fields. Here we demonstrate active magnetic-field control over lasing in a periodic array of Co/Pt multilayer nanodots immersed in an IR-140 dye solution. We exploit the magnetic nature of the nanoparticles combined with mode tailoring to control the lasing action. Under circularly polarized excitation, angle-resolved photoluminescence measurements reveal a transition between the lasing action and non-lasing emission as the nanodot magnetization is reversed. Our results introduce magnetization as a means of externally controlling plasmonic nanolasers, complementary to modulation by excitation(5), gain medium(6)(.7) or substrate(8). Further, the results show how the effects of magnetization on light that are inherently weak can be observed in the lasing regime, inspiring studies of topological photonics(9-11)