Highly efficient photocatalytic H evolution over NiCoS/MnCdS: Bulk twinned homojunctions and interfacial heterojunctions.

A twinned MnCdS (T-MCS) homojunction, consisting of wurtzite and zinc-blende MnCdS with different energy band structures, was fabricated using a facile hydrothermal method, resulting in the formation of a type-II bulk phase twinned homojunction. Furthermore, NiCoS nanoparticles were deposited on the surface of T-MCS to form a surface heterojunction. The activities of T-MCS and NiCoS/T-MCS were tested in the photocatalytic H evolution reaction.

High-sensitivity broad free-spectral-range two-dimensional three-slot photonic crystal sensor integrated with a 1D photonic crystal bandgap filter.

We present a novel high-sensitivity broad free-spectral-range (FSR) two-dimensional three-slot photonic crystal sensor integrated with a 1D photonic crystal tapered nanobeam bandgap filter (1DPC-TNBF) based on thin-film silicon. Designed to lie in the wavelength at around 1550 nm, the resonance of the two-dimensional photonic crystal three-slot cavity (2DPC-TSC) shows strong light-matter interaction in the slot region, which enhances the bulk refractive index sensitivity of the sensor significantly. The simulated sensitivity is over 900 nm/refractive index unit (RIU).

Ultra-compact air-mode photonic crystal nanobeam cavity integrated with bandstop filter for refractive index sensing.

We propose and investigate an ultra-compact air-mode photonic crystal nanobeam cavity (PCNC) with an ultra-high quality factor-to-mode volume ratio (Q/V) by quadratically tapering the lattice space of the rectangular holes from the center to both ends while other parameters remain unchanged. By using the three-dimensional finite-difference time-domain method, an optimized geometry yields a Q of 7.2×10 and a V∼1.

Higher Q factor and higher extinction ratio with lower detection limit photonic crystal-parallel-integrated sensor array for on-chip optical multiplexing sensing.

We introduce an alternative method to establish a nanoscale sensor array based on a photonic crystal (PhC) slab, which is referred to as a 1×4 monolithic PhC parallel-integrated sensor array (PhC-PISA). To realize this function, four lattice-shifted resonant cavities are butt-coupled to four output waveguide branches, respectively. By shifting the first to the two closest neighboring holes around the defect, a high Q factor over 1.

Multiplexed Simultaneous High Sensitivity Sensors with High-Order Mode Based on the Integration of Photonic Crystal 1 × 3 Beam Splitter and Three Different Single-Slot PCNCs.

We simulated an efficient method for the sensor array of high-sensitivity single-slot photonic crystal nanobeam cavities (PCNCs) on a silicon platform. With the combination of a well-designed photonic crystal waveguide (PhCW) filter and an elaborate single-slot PCNC, a specific high-order resonant mode was filtered for sensing. A 1 × 3 beam splitter carefully established was implemented to split channels and integrate three sensors to realize microarrays.