Exceptional points (EPs) in the polarization space were observed in reflection on helically structured thin films. These films have form anisotropy at the nanoscale introduced through dynamic control of crystalline growth geometry by changing the orientation of the substrate with respect to the impinging vapor. They are simpler alternatives to metasurfaces, because they can be produced at low cost using conventional thin-film deposition techniques. The EPs were experimentally confirmed by eigenstate swapping on a closed circuit surrounding them and were predicted by numerical calculations. Reflective surfaces operating at an EP could be used to make ultrasensitive sensors.

Download full-text PDF

Source
http://dx.doi.org/10.1364/OL.430207DOI Listing

Publication Analysis

Top Keywords

exceptional points
8
helically structured
8
structured thin
8
thin films
8
observation exceptional
4
points helically
4
films exceptional
4
points eps
4
eps polarization
4
polarization space
4

Similar Publications

Stress Relaxation for Lead Iodide Nucleation in Efficient Perovskite Solar Cells.

Adv Mater

January 2025

Key Lab of Artificial Micro- and Nano-Structures of Ministry of Education of China, School of Physics and Technology, Wuhan University, Wuhan, 430072, China.

Porous lead iodide (PbI) film is crucial for the complete reaction between PbI and ammonium salts in sequential-deposition technology so as to achieve high crystallinity perovskite film. Herein, it is found that the tensile stress in tin (IV) oxide (SnO) electron transport layer (ETL) is a key factor influencing the morphology and crystallization of PbI films. Focusing on this, lithium trifluoromethanesulfonate (LiOTf) is used as an interfacial modifier in the SnO/PbI interface to decrease the tensile stress to reduce the necessary critical Gibbs free energy for PbI nuclei formation.

View Article and Find Full Text PDF

Topological bound states in the continuum in a non-Hermitian photonic system.

Nanophotonics

January 2025

Department of Electronic Engineering, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.

Topological insulators and bound states in the continuum represent two fascinating topics in the optical and photonic domain. The exploration of their interconnection and potential applications has emerged as a current research focus. Here, we investigated non-Hermitian photonics based on a parallel cascaded-resonator system, where both direct and indirect coupling between adjacent resonators can be independently manipulated.

View Article and Find Full Text PDF

Novel p.Arg534del Mutation and MTHFR C667T Polymorphism in Fragile X Syndrome (FXS) With Autism Spectrum Phenotype: A Case Report.

Case Rep Genet

January 2025

Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California, 2825 50th Street, Davis, Sacramento 95817, California, USA.

Fragile X syndrome (FXS) presents with autism spectrum disorder (ASD), intellectual disability, developmental delay, seizures, hypotonia during infancy, joint laxity, behavioral issues, and characteristic facial features. The predominant mechanism is due to CGG trinucleotide repeat expansion of more than 200 repeats in the 5'UTR (untranslated region) of (Fragile X Messenger Ribonucleoprotein 1) causing promoter methylation and transcriptional silencing. However, not all patients presenting with the characteristic phenotype and point/frameshift mutations with deletions in have been described in the literature.

View Article and Find Full Text PDF

An automatic and real-time echocardiography quality scoring system based on deep learning to improve reproducible assessment of left ventricular ejection fraction.

Quant Imaging Med Surg

January 2025

Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China.

Background: Echocardiography can conveniently, rapidly, and economically evaluate the structure and function of the heart, and has important value in the diagnosis and evaluation of cardiovascular diseases (CVDs). However, echocardiography still exhibits significant variability in image acquisition and diagnosis, with a heavy dependency on the operator's experience. Image quality affects disease diagnosis in the later stage, and even image quality assessment still has variability in human evaluation.

View Article and Find Full Text PDF

Point-of-care testing of methotrexate using a controlled release sensor based on a personal glucose meter.

Anal Methods

January 2025

Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044, PR China.

Methotrexate (MTX), a widely administered medication for treating an array of tumors and autoimmune disorders, necessitates stringent monitoring due to the potential for severe adverse effects associated with its high dosage. Nevertheless, the existing methods for monitoring MTX are often intricate, time-consuming and incur significant costs. In this work, we constructed a controlled release sensor, harnessing the versatility of a personal glucose meter (PGM), which had been devised for the swift detection of MTX.

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!