Sharp electromagnetic resonances play an essential role in physics general and optics particular. The last decades have witnessed the successful developments of high-quality (Q) microcavities operating below light line, which however is fundamentally challenging to access from free space. Alternatively, metasurface-based bound states continuum (BICs) offer a complementary solution creating high-Q devices above yet experimentally demonstrated Q factors under normal excitations are still...

As one of the most important semiconductors, silicon has been used to fabricate electronic devices, waveguides, detectors, solar cells, etc. However, indirect bandgap and low quantum efficiency (10-7) hinder use for making good emitters. For integrated photonic circuits, silicon-based emitters with sizes in range 100-300 nm are highly desirable. Here, we show electric magnetic resonances nanoparticles enhance demonstrate white-light emission from feature ~200 nm. The dipole employed...

Abstract Efficient frequency up-conversion of coherent light at the nanoscale is highly demanded for a variety modern photonic applications, but it remains challenging in nanophotonics. Surface second-order nonlinearity noble metals can be significantly boosted up by plasmon-induced field enhancement, however related far-field second-harmonic generation (SHG) may also quenched symmetric plasmonic nanostructures despite huge near-field amplification. Here, we demonstrate that SHG from single...

Abstract In this study, the photothermal effect and up-conversion florescence imaging of gold nanobipyramids in liver cancer cells are investigated theoretically experimentally to explore ablation tumor therapy with higher conversion efficiency, shorter laser action time, smaller range lower power. The small-size good biocompatibility infrared absorption peak located first biological window synthesized. Femtosecond is focused on clusters die after being irradiated for 20 s at a power as low...

The authors demonstrate experimentally that interaction between nonlocal solitons in nematic liquid crystals (NLCs) can be controlled by the degree of nonlocality. For a given beam width, nonlocality modulated changing pretilt angle θ0 NLC molecules through bias voltage V. As V increases (so does θ0), decreases. When is below critical value, behave way like their local counterpart, i.e., in-phase attract while out-of-phase repulse each other. Such voltage-controlled readily implemented experiments.

The fractional Fourier transform (FRFT) naturally exists in strongly nonlocal nonlinear (SNN) media and the propagation of optical beams SNN can be simply regarded as a self-induced FRFT. Through FRFT technique evolution fields conveniently dealt with, an arbitrary square-integrable input field presents itself generally revivable higher-order spatial soliton which reconstructs its profile periodically after every four transforms. illuminates prospects for new applications such continuously...

The high spatial frequency periodic structures induced on metal surface by femtosecond laser pulses was investigated experimentally and numerically. It is suggested that the redistribution of electric field caused initially formed low plays a crucial role in creation structures. intensity which localized grooves becomes concentrated ridges between when depth exceeds critical value, leading to ablation formation proposed process supported both numerical simulations based finite-difference...

Gold (Au) nanoparticles, particularly nanorods, are actively employed as imaging probes because of their special nonblinking and nonbleaching absorption, scattering, emitting properties that arise from the excitation surface plasmons. Herein, we report a novel sensing method detects feature orientation at nanoscale via defocused individual Au nanorods (AuNRs) with an ordinary wide-field optical microscope. By simultaneously recording images two-photon luminescence intensities for large...

Abstract Bound states in the continuum (BIC) are considered as an effective means to dramatically elongate trapping time of light. However, light-matter interaction depends not only on life-time optical mode, but also its mode volume. Therefore, increasing and minimizing volume simultaneously, utilizing BIC resembles a promising way for enhancing interaction. Herein, we have proposed novel hybrid plasmonic-dielectric structure manipulate BIC. For Friedrich-Wintgen BIC, electric field is...

The low quantum efficiency of silicon (Si) has been a long-standing challenge for scientists. Although improvement achieved in porous Si or dots, highly efficient Si-based light sources prepared by using the current fabrication technooloy chips are still being pursued. Here, we proposed strategy, which exploits intrinsic excitation carriers at high temperatures, to modify carrier dynamics nanoparticles. We designed Si/SiO

Based on the Snyder-Mitchell model in Cartesian coordinate system, exact analytical Hermite-Gaussian (HG) solutions are obtained strongly nonlocal nonlinear media. The comparisons of with numerical simulations Schrödinger equation show that HG good agreement case strong nonlocality. Furthermore, we demonstrate functions can be expressed as a linear superposition individual Gaussian π phase difference under appropriate conditions.

Based on the excitation of surface plasmon polaritons (SPPs), we analytically and numerically investigate transmission response in metal-dielectric-metal (MDM) plasmonic waveguides with a side coupled nanocavity (SCNC). By filling Kerr nonlinear medium, position resonant dip spectrum can be tuned by incident light intensity. The oscillation Fabry-Perot formed incorporating finite length same media into MDM waveguide acts as background for system induces sharp asymmetric line shape. As...

A simple fiber sensor for magnetic field measurement based on nanoparticle Fe(3)O(4) fluid and relative Fresnel reflection is presented. The includes only a light source, three couplers, two photodetectors, sensing ends. Magnetic fields at different concentrations of are measured. with high concentration can be used the weak fields, while low strong fields. temperature dependence also addressed.

Periodic surface structures with periods as small about one-tenth of the irradiating femtosecond (fs) laser light wavelength were created on a titanium (Ti) foil by exploiting laser-induced oxidation and third harmonic generation (THG). They achieved using 100-fs pulses repetition rate 1 kHz ranging from 1.4 to 2.2 μm. It was revealed that an extremely thin TixOy layer formed Ti after fs fluence smaller than ablation threshold Ti, leading significant enhancement in THG which may exceed...

We report on the formation of one- and two-dimensional (1D 2D) nanohole arrays surface a silicon wafer by scanning with femtosecond laser appropriate power speed. The underlying physical mechanism is revealed numerical simulation based finite-difference time-domain technique. It found that length depth initially formed gratings (or ripples) plays crucial role in generation 1D or 2D arrays. decorated such can exhibit vivid structural colors through efficiently diffracting white light.

Data storage with ultrahigh density, ultralow energy, high security, and long lifetime is highly desirable in the 21st century optical data considered as most promising way to meet challenge of storing big data. Plasmonic coupling regularly arranged metallic nanoparticles has demonstrated its superior properties various applications due generation hot spots. Here, discovery polarization spectrum sensitivity random spots generated a volume gold nanorod assembly reported. It that...

Abstract Realizing and manipulating strong light–matter coupling in 2D monolayer semiconductors is of paramount importance the development novel photonic devices. Here, it revealed by numerical simulation that between excitons a WS 2 surface plasmon polaritons propagating on thin Au film can be realized when are generated via Kretschmann–Raether configuration. The use liquid Ga nanoparticles, which exhibit broad scattering spectra visible light, proposed to identify exciton–plasmon coupling....

Abstract Optical pulling provides a new degree of freedom in optical manipulation. It is generally believed that long-range forces cannot be generated by the gradient incident field. Here, we theoretically propose and numerically demonstrate realization force stemming from self-induced field manipulated object. In analogy to potential barriers quantum tunnelling, use photonic band gap design order obtain intensity gradients inside object placed crystal waveguide, thereby achieving force....

The interaction between ultrafast, tightly focused lasers and materials has garnered significant interest owing to its distinctive properties. In this study, we present a versatile methodology for the fabrication of tunable plasmonic nanostructures by employing disordered gold nanoisland-dielectric-metal configuration, achieved through femtosecond laser printing. By reshaping nanoislands reconfiguring them into nanograting-like structures, orientation these is influenced polarization light,...