Related Experiment Video
Updated: Jun 6, 2026

Recombination Dynamics in Thin-film Photovoltaic Materials via Time-resolved Microwave Conductivity
Published on: March 6, 2017
Accurate coupling coefficients for fiber couplers with weakly fused cross sections
Abstract:
For fused tapered fiber couplers with weakly fused cross sections, power coupling takes place between two touching tapered cladding cylinders embedded in the air, and the cylinders then become a strongly guiding structure. We provide accurate polarization-dependent coupling coefficients for such a structure, on the basis of a rigorous vectorial numerical calculation. Our results for the corresponding weakly guiding structure are compared with previous vector perturbation methods base on scalar fields. It is found that the scalar theories are not applicable to those cases with large normalized frequencies or with small fiber separations when the polarization-splitting effect is concerned.
Related Concept Videos
Spin–Spin Coupling Constant: Overview
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must have a...
Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)
The extent of coupling depends on the C‑C bond length, the two H‑C‑C angles, any electron-withdrawing substituents, and the dihedral angle between the involved orbitals. The...
¹H NMR: Long-Range Coupling
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene π orbitals.
Bending of Members Made of Several Materials
Hooke's Law determines stress in each material, stating that stress is proportional to strain but varies due to each material's...
Transmission Line Design Considerations
Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...

