The realization of an efficient optical sensor based on a photonic crystal metasurface supporting bound states in the continuum is reported. Liquids with different refractive indices, ranging from 1.4000 to 1.4480, are infiltrated microfluidic chamber bonded sensing dielectric metasurface. A bulk liquid sensitivity 178 nm/RIU achieved, while Q-factor about 2000 gives figure merit up 445 air at both visible and infrared excitations. Furthermore, detection ultralow-molecular-weight (186 Da)...

Abstract Photonic bound states in the continuum (BICs), embedded spectrum of free-space waves 1,2 with diverging radiative quality factor, are topologically non-trivial dark modes open-cavity resonators that have enabled important advances photonics 3,4 . However, it is particularly challenging to achieve maximum near-field enhancement, as this requires matching and non-radiative losses. Here we propose concept supercritical coupling, drawing inspiration from electromagnetically induced...

We studied a novel family of paraxial laser beams forming an overcomplete yet nonorthogonal set modes. These modes have singular phase profile and are eigenfunctions the photon orbital angular momentum. The intensity is characterized by single brilliant ring with singularity at its center, where field amplitude vanishes. complex proportional to degenerate (confluent) hypergeometric function, therefore we term such hypergeometric-Gaussian (HyGG) Unlike recently introduced [Opt. Lett. 32, 742...

Plasmonic substrates play a crucial role in the confinement and manipulation of localized electromagnetic fields at nanoscale. The large field enhancement metal/dielectric interfaces is widely exploited surface-enhanced fluorescence (SEF) Raman scattering (SERS) spectroscopies. Despite advantage near-field enhancement, unfortunately, metals, absorption optical frequencies induces local heating analyte fluid with possible damage biological material. In addition, SEF plasmonic substrates,...

Herein, we demonstrate a cavity-enhanced hyperspectral refractometric imaging using an all-dielectric photonic crystal slab (PhCS). Our approach takes advantage of the synergy between two mechanisms, surface-enhanced fluorescence (SEF) and sensing, both based on high-Q resonances in proximity bound states continuum (BICs). The enhanced local optical field first resonance amplifies 2 orders magnitude SEF emission probe dye. Simultaneously, Fano interference second mode emission, is used for...

In this work, we investigate the evanescent field sensing mechanism provided by an all-dielectric metasurface supporting bound states in continuum (BICs).The is based on a transparent photonic crystal with subwavelength thickness.The BIC electromagnetic localized along direction normal to nanoscale-thin slab (PhCS) because of topology-induced confinement, exponentially decaying material detect.On other hand, it totally delocalized PhCS plane, which favors versatile and multiplexing...

A compact and robust scheme for broadband excitation of whispering gallery mode (WGM) resonances into a microsphere is demonstrated. polymer (10 μm) encapsulated the capillary microstructured optical fiber, in direct contact with guiding core. Such configuration allows efficient reproducible in-MOF-microsphere resonator that characterized by two launch/collection schemes: core input/scattering output, sphere input/core output. The latter an WGMs externally to fiber. Numerically calculated...

In this paper we report on the engineering of repeatable surface enhanced Raman scattering (SERS) optical fiber sensor devices (optrodes), as realized through nanosphere lithography. The Lab-on-Fiber SERS optrode consists polystyrene nanospheres in a close-packed arrays configuration covered by thin film gold tip. surfaces were fabricated using lithography approach that is already demonstrated able to produce highly patterns order engineer and optimize probes, first evaluated compared...

Label-free, surface-enhanced Raman spectroscopic imaging of the challenging red blood cell membrane is achieved by using a near-hyperuniform disordered plasmonic nanostructure silver nanoparticles.

We report on the self-assembling of clusters gold-nanoparticles (Au-NPs) directed by phase separation poly(styrene)-b-poly(methylmethacrylate) (PS-b-PMMA) block-copolymer (BCP) indium tin oxide coated glass, which induces onset vertical lamellar domains. After thermal evaporation gold BCP, Au-NPs 4 nm are selectively included into PS-nanodomains annealing, and then clustered with large density hot spots (> 10(4) μm(2)) in a random two-dimensional pattern. The resulting nanostructure exhibits...

Abstract The small molecule Galunisertib (LY2157299, LY) shows multiple anticancer activities blocking the transforming growth factor‐β1 receptor, responsible for epithelial‐to‐mesenchymal transition (EMT) by which colorectal cancer (CRC) cells acquire migratory and metastatic capacities. However, frequent dosing of LY can produce highly toxic metabolites. Alternative strategies to reduce drug side effects rely on nanoscale delivery systems that have led a medical revolution in treatment...

We developed an immunoassay platform for the detection of human Thyroglobulin (Tg) to be integrated with fine-needle aspiration biopsy early lymph node metastases in thyroid cancer patients. The sensing detects Tg by a sandwich involving self-assembled surface-enhanced Raman scattering (SERS) substrate assisted functionalized gold nanoparticles that provide additional signal amplification and improved molecular specificity. Specifically, SERS-active substrates were Capture antibodies...

The analysis of leukocytes peripheral blood is a crucial step in hematologic exams commonly used for disease diagnosis and, typically, requires molecular labelling. In addition, only detailed, laborious phenotypic allows identifying the presence and stage specific pathologies such as leukemia. Most biochemical information lost routine tests. present study, we tackle 2 important issues label-free identification classification using Raman spectroscopy (RS). First, demonstrate that leukocyte...

Tip-enhanced Raman Scattering (TERS) has recently emerged as a powerful spectroscopic technique capable of providing subdiffraction morphological and chemical information on samples. In this work, we apply TERS spectroscopy for surface analysis the Bacillus subtilis spore, very attractive biosystem wide range applications regulated by spore properties. The observed spectra reflect complex heterogeneous environment explored plasmonic tip, therefore exhibiting significant point-to-point...

In this work, we propose the use of complex, bioderived nanostructures as efficient surface-enhanced Raman scattering (SERS) substrates for chemical analysis cellular membranes. These structures were directly obtained from a suitable gold metalization Pseudonitzchia multistriata diatom silica shell (the so called frustule), whose grating-like geometry provides large light coupling with external radiation, whereas its extruded, subwavelength lateral edge an excellent interaction cells without...

Abstract The ability to control light at the nanoscale is basis of contemporary photonics and plasmonics. In particular, properly engineered periodic nanostructures not only allow inhibition propagation specific spectral ranges or its confinement in nanocavities waveguides, but make also possible field enhancement effects vibrational, Raman, infrared fluorescence spectroscopies, paving way development novel high-performance optical sensors. All these devices find an impressive analogy...

Spin-polarized directive coupling of light associated with the photonic quantum spin-Hall effect (QSHE) is a nanoscale phenomenon based on strong spin-orbit interaction that has recently attracted significant attention.Herein, we discuss experimental manifestation QSHE intrinsic in Bloch waves bound state continuum (BIC) dielectric crystal metasurface (PhCM).We show numerically BICs PhCMs have spin angular momentum density transverse to orbital not only at interfaces but also inside...

Abstract Photonics bound states in the continuum (BICs) are peculiar localized of free‐space waves, unaffected by far‐field radiation loss. Although plasmonic nano‐antennas squeeze optical field to nanoscale volumes, engineering emergence quasi‐BICs with hotspots remains challenging. Here, origin symmetry‐protected (SP) a 2D system silver‐filled dimers, quasi‐embedded high‐index dielectric waveguide, is investigated through strong coupling between photonic and modes. By tailoring hybridizing...

Recently important efforts have been dedicated to the realization of a new kind photonic crystals, known as quasicrystals, in which lack translational symmetry is compensated by rotational symmetries not achievable conventional periodic crystals.Here we show novel approach their fabrication based on use programmable Spatial Light Modulator encoding Computer-Generated Holograms.Using this single beam technique fabricated Penrose-tiled structures possessing up 23-fold, and twodimensional...

Disordered hyperuniform (DH) media have been recognized as a new state of disordered matter that broadens our vision material engineering. Here, long-range correlated two-dimensional patterns are fabricated by self-assembling spherical diblock-copolymer (BCP) micelles. Control the parameters leads to formation DH micelles can host nanoscale inclusions, therefore providing an effective strategy for fabricating multimaterial structures at molecular scale. Centroidal accurately determined...

Abstract Large-area and transparent all-dielectric metasurfaces sustaining photonic bound states in the continuum (BICs) provide a set of fundamental advantages for ultrasensitive biosensing. BICs bridge gap large effective mode volume with experimental quality factor. Relying on transduction mechanism reactive sensing principle, herein, we first numerically study potential subwavelength confinement driven by topological decoupling from free space radiation BIC-based Then, experimentally...

Circulating tumor cells (CTCs) are that have penetrated the circulatory system preserving properties and heterogeneity. Detection characterization of CTCs has high potential clinical values many technologies been developed for CTC identification. These approaches remain challenged by extraordinary rarity difficulty efficiently distinguishing cancer from much larger number white blood in bloodstream. Consequently, there is still a need efficient rapid methods to capture broad spectrum...

Abstract The integration of advanced materials and photonic nanostructures can lead to enhanced biodetection capabilities, crucial in clinical scenarios point‐of‐care diagnostics, where simplified strategies are essential. Herein, a molecularly imprinted polymer (MIP) nanostructure is demonstrated, which selectively binding transforming growth factor‐beta (TGF‐β), the sensing transduction by bound states continuum (BICs). MIP operating as synthetic antibody matrix coupled with BIC resonance,...