Exact transformation optics by using electrostatics.

Sci Bull (Beijing)

Institute of Electromagnetics and Acoustics and Department of Physics, College of Physical Science and Technology, Xiamen University, Xiamen 361005, China. Electronic address:

Published: February 2022

We present a novel method for designing transformation optical devices based on electrostatics. An arbitrary transformation of electrostatic field can lead to a new refractive index distribution, where wavefronts and energy flux lines correspond to equipotential surfaces and electrostatic flux lines, respectively. Owing to scalar wave propagating exactly following an eikonal equation, wave optics and geometric optics share the same solutions in the devices. The method is utilized to design multipole lenses derived from multipoles in electrostatics. The source and drain in optics are considered as corresponding to positive charge and negative charge in the static field. By defining winding numbers in virtual and physical spaces, we explain the reason for some multipole lenses with illusion effects. Besides, we introduce an equipotential absorber to replace the drain to correspond to a negative charge with a grounded conductor. Therefore, it is a very general platform to design intriguing devices based on the combination of electrostatics and transformation optics.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.scib.2021.09.017DOI Listing

Publication Analysis

Top Keywords

transformation optics
8
devices based
8
flux lines
8
multipole lenses
8
negative charge
8
optics
5
exact transformation
4
electrostatics
4
optics electrostatics
4
electrostatics novel
4

Similar Publications

CSPG4 overexpression implicates higher risks of recurrence and tumorigenesis after surgical intervention of vocal fold Leukoplakia.

Eur Arch Otorhinolaryngol

January 2025

ENT institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, 83 FenYang Road, Shanghai, 200031, China.

Background: Vocal fold leukoplakia (VFL), a precancerous lesion of the larynx, is characterized by white plaques on the vocal fold mucous membrane. Currently, there are no reliable biomarkers to predict the recurrence and malignant transformation of VFL. Considering chondroitin sulfate proteoglycan 4 (CSPG4) as a biomarker for malignant tumors such as laryngeal squamous cell carcinoma (LSCC), we conducted this cohort study to evaluate the prognostic influence of CSPG4 expression on VFL patients.

View Article and Find Full Text PDF

Bacterial contamination is a very serious health and environmental problem, with the main source of toxicity being lipopolysaccharides in the cell walls of Gram-negative bacteria. Therefore, the development of effective analytical methods is crucial for the detection of lipopolysaccharide content. This work facilitates the efficient generation of precisely adjustable dual-mode signals for LPS detection in surface-enhanced Raman spectroscopy (SERS) and electrochemiluminescence (ECL) by inducing anisotropic morphological evolution of Au@Ag nanocubes (Au@AgNCs) through poly-cytosine (poly-C) DNA.

View Article and Find Full Text PDF

Photoassisted lithium-sulfur (Li-S) batteries offer a promising approach to enhance the catalytic transformation kinetics of polysulfide. However, the development is greatly hindered by inadequate photo absorption and severe photoexcited carriers recombination. Herein, a photonic crystal sulfide heterojunction structure is designed as a bifunctional electrode scaffold for photoassisted Li-S batteries.

View Article and Find Full Text PDF

This paper presents an approach for event recognition in sequential images using human body part features and their surrounding context. Key body points were approximated to track and monitor their presence in complex scenarios. Various feature descriptors, including MSER (Maximally Stable Extremal Regions), SURF (Speeded-Up Robust Features), distance transform, and DOF (Degrees of Freedom), were applied to skeleton points, while BRIEF (Binary Robust Independent Elementary Features), HOG (Histogram of Oriented Gradients), FAST (Features from Accelerated Segment Test), and Optical Flow were used on silhouettes or full-body points to capture both geometric and motion-based features.

View Article and Find Full Text PDF

In a search for dyes photoactivatable with visible light, fluorenes with substituents at positions 2 and 7 were prepared, and their absorption and emission spectra were studied. In particular, the synthesis route to 9-diazofluorenes with 2-(N,N-dialkylamino) and N-modified 7-(4-pyridyl) substituents was established. These compounds are initially non-fluorescent, undergo photolysis with UV or blue light, and-in non-polar media-provide orange- to red-emitting products with a large separation between absorption and emission bands.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!