Modulation is a cornerstone of optical communication, and as such, governs the overall speed data transmission. Currently, two main strategies for modulating light are direct modulation excited emitter population (for example, using semiconductor lasers) external Mach-Zehnder interferometers or ring resonators). However, recent advances in nanophotonics offer an alternative approach to control spontaneous emission through modifications local density states. Here, by leveraging phase-change...

Due to the scarcity of circular polarization light sources, linear-to-circular conversion is required generate circularly polarized for a variety applications. Despite significant past efforts, broadband remains elusive particularly in terahertz and midinfrared frequency ranges. Here we propose novel mechanism based on coupled mode theory, experimentally demonstrate at frequencies that highly efficient (power efficiency approaching unity) ultrabroadband (fractional bandwidth up 80%) can be...

Co(1-x)M(x)Cr(2)O(4) (M = Li, Zr; x 0-0.2) catalysts were prepared via the citric acid method and investigated for catalytic combustion of methane. Substitution at tetrahedral (A) sites with monovalent (Li) or tetravalent (Zr) metal ions led to a decrease increase activity, respectively. The Co(0.95)Zr(0.05)Cr(2)O(4) catalyst proved be most active its activity reached 90% methane conversion 448 °C, which dropped by 66 °C compared that undoped CoCr(2)O(4) catalyst. XRD Raman results indicated...

Enhancing the gating performance of single-molecule conductance is significant for realizing molecular transistors. Herein, we report a new strategy to improve electrochemical efficiency with fused structures consisting heterocyclic rings furan, thiophene, or selenophene. One order magnitude ratio achieved within potential window 1.2 V selenophene-based molecule, which significantly greater than that other and benzene ring molecules. This caused by different electronic molecules transmission...

We experimentally quantify the contribution of magnetic dipole (MD) transitions to near-infrared light emission from trivalent erbium-doped yttrium oxide (Er${}^{3+}$:Y${}_{2}$O${}_{3}$). Using energy-momentum spectroscopy, we demonstrate that ${}^{4}$I${}_{13/2}{\ensuremath{\rightarrow}}^{4}$I${}_{15/2}$ near 1.5 $\ensuremath{\mu}$m originates nearly equal contributions electric (ED) and MD exhibit distinct spectra. then show how these spectra, together with differing local density optical...

Surface plasmon polaritons can make incoherent light coherent and vice versa.

Abstract Integration of nanoscale photonic and plasmonic components on Si substrates is a critical step toward Si‐based integrated nanophotonic devices. In this work, set unique complex 3D metamaterials with intercalated nanolayered nanopillar structures tunable optical properties designed. More specifically, the combine metal (Au) nanopillars alternating metal‐nitride (Au‐TiN Au‐TaN) nanolayers, epitaxially grown substrates. The ultrafine Au ( d ≈ 3 nm) continuously grow throughout all...

We experimentally demonstrate that the radiative decay rate of a quantum emitter is determined by combined electric and magnetic local density optical states (LDOS). A Drexhage-style experiment was performed for two distinct emitters, divalent nickel ions in magnesium oxide trivalent erbium yttrium oxide, which both support nearly equal mixtures isotropic dipole transitions. The disappearance lifetime oscillations as function emitter-interface separation distance confirms electromagnetic...

Abstract Optical interferometry has empowered an impressive variety of biosensing and medical imaging techniques. A widely held assumption is that devices based on optical require coherent light to generate a precise signature in response analyte. Here we disprove assumption. By directly embedding emitters into subwavelength cavities plasmonic interferometers, demonstrate generation surface plasmons even when with extremely low degrees spatial temporal coherence employed. This surprising...

The enhanced optical forces induced by surface phonon-polariton (SPhP) modes are investigated in different silicon carbide (SiC) nanostructures. Specifically, we calculate using the Maxwell stress tensor for three geometries: spherical particles, slab waveguides, and rectangular waveguides. We show that SPhP SiC can produce very large forces, more than one order of magnitude larger plasmon-polariton (SPP) analogous metal material geometric basis these examined terms dispersive permittivity,...

We present a method to simultaneously engineer the energy-momentum dispersion and local density of optical states (LDOS). Using vertical symmetry breaking in high-contrast gratings, we enable mixing modes with different parities, thus producing hybridized controlled dispersion. By tuning geometric parameters, control coupling between Bloch modes, leading flatband, M- W-shaped as well Dirac This dispersion-engineering leads tailored LDOS experimentally demonstrate two order magnitude...

Microstructural control in metal-dielectric hybrid metamaterials presents enormous opportunities tailoring the physical properties including magnetic and optical properties. Here, we demonstrate a strong tunability achieved microstructure of self-assembled ordered three-phase Au-BaTiO3–ZnO metamaterial along with its properties, grown by pulsed laser deposition method. Varying growth temperature, frequency, template thickness evolves tuning Au ZnO pillar geometry as well shape size...

Germanium (Ge) quantum dot (QD) photodetectors (PDs) were fabricated on Ge substrates exhibiting a broadband, visible to near-infrared (near-IR) photoresponse in the λ = 400–1550 nm range. Room-temperature responsivities (Rsp) up 1.12 A/W and internal efficiency IQE 313% obtained, superior conventional silicon germanium photodiodes. Noise analysis was performed at 640 telecom 1550 wavelengths, both yielding room-temperature specific detectivity D* ≃ 2 × 1010 cm Hz1/2 W−1. Lowering operating...

Light emission is defined by its distribution in energy, momentum, and polarization. Here, we demonstrate a method that resolves these distributions means of wide-angle energy-momentum spectroscopy. Specifically, image the back focal plane microscope objective through Wollaston prism to obtain polarized Fourier-space momentum distributions, disperse two-dimensional radiation patterns an imaging spectrograph without entrance slit. The resulting measurements represent convolution individual at...

A class of plasmonic interferometers consisting a circular slit flanked by concentric groove is demonstrated. Laying in-between the conventional bullseye and linear slit-groove interferometers, these show polarization-insensitive optical response (thanks to rotational symmetry imposed geometry), overall higher light transmission (due absence cutoff condition in subwavelength slit). Light sensitivity can be further enhanced presence resonant modes excited slit. The proposed employed develop...

The temperature‐dependent operation of high efficiency Ge quantum dot (QD) photodetectors (PDs) is reported, that shows spectral responsivity 1.2 A W −1 , internal (IQE) 228% and signal‐to‐noise ratio (SNR) equal to 7 × 10 6 at a wavelength 640 nm for 12 μW incident power. performance these can be improved by reducing the operating temperature, especially low For instance, nW illumination power, lowering temperature from 300 100 K improves SNR 2 4 5 specific detectivity D* 11 13 cm Hz 1/2 ....

Tetragonal tungsten bronze (TTB) materials are one of the most promising classes for ferroelectric and nonlinear optical devices, owing to their very unique noncentrosymmetric crystal structure. In this work, a new TTB phase LiNb6Ba5Ti4O30 (LNBTO) has been discovered studied. A small amount secondary phase, LiTiO2 (LTO), incorporated as nanopillars that vertically embedded in LNBTO matrix. The multifunctional nanocomposite thin film presents exotic highly anisotropic microstructure...

We compare the intensity modulation of passive light transmission and active fluorescence emission in planar plasmonic interferometers consisting a nano-scale hole flanked by circular grooves etched silver film. Discrete fast Fourier transform applied to interferograms - i.e., optical obtained varying propagation phase surface plasmon polaritons (SPPs) reveals higher-order interference effects that can be enhanced optimizing in-plane SPP scattering reflection. The experimental dispersion...

We demonstrate the feasibility to control confined electromagnetic field by surface plasmon poloritons (SPPs) excitation and scattering modulation based on pre-processed Au nanostructures under irradiation of single-shot femtosecond (fs) laser pulse, then tension-induced molten Si transport due directed lateral temperature profile, thus resulting in formation nanostructures. Annular-shaped fs pulse is employed nonlinear optical effect frequency-doubling process imprint planar with various...