Several chalcogenide alloys exhibit a pronounced contrast between the optical absorption in the metastable rocksalt and in the amorphous phase. This phenomenon is the basis for their application in optical data storage. Here we present ab initio calculations of the optical properties of GeTe and Ge1Sb2Te4 in the two phases. The analysis of our computations and experimental data reveal the correlation between local structural changes and optical properties as well as the origin of the optical contrast in these materials. We find that the change in optical properties cannot be attributed to a smearing of transition energies as commonly assumed for amorphous semiconductors: the optical contrast between the two phases can only be explained by significant changes in the transition matrix elements.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1103/PhysRevLett.98.236403 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Sialic Acid-Modified NIR-II Fluorophore with Enhanced Brightness and Photoconversion Capability for Targeted Lymphoma Phototheranostics.
Anal Chem
January 2025
School of Life Sciences, Key Laboratory of Space Bioscience & Biotechnology, Northwestern Polytechnical University, Xi'an 710072, China.
Lymphoma is a malignant cancer characterized by a rapidly increasing incidence, complex etiology, and lack of obvious early symptoms. Efficient theranostics of lymphoma is of great significance in improving patient outcomes, empowering informed decision-making, and driving medical innovation. Herein, we developed a multifunctional nanoplatform for precise optical imaging and therapy of lymphoma based on a new photosensitizer (1-oxo-1-benzoo[de]anthracene-2,3-dicarbonitrile-triphenylamine (OBADC-TPA)).
View Article and Find Full Text PDFViral Transcript and Tumor Immune Microenvironment-Based Transcriptomic Profiling of HPV-Associated Head and Neck Squamous Cell Carcinoma Identifies Subtypes Associated with Prognosis.
Viruses
December 2024
Department of Otolaryngology-Head and Neck Surgery, Harvard Medical School, Boston, MA 02115, USA.
Human papillomavirus (HPV)-associated head and neck squamous cell carcinoma (HPV-positive HNSCC) has distinct biological characteristics from HPV-negative HNSCC. Using an AI-based analytical platform on meta cohorts, we profiled expression patterns of viral transcripts and HPV viral genome integration, and classified the tumor microenvironment (TME). Unsupervised clustering analysis revealed five distinct and novel TME subtypes across patients (immune-enriched, highly immune and B-cell enriched, fibrotic, immune-desert, and immune-enriched luminal).
View Article and Find Full Text PDFChanneled Polarimetry for Magnetic Field/Current Detection.
Sensors (Basel)
January 2025
Institute of Optical Materials and Technologies, Bulgarian Academy of Sciences, 109, Acad. G. Bonchev Str., 1113 Sofia, Bulgaria.
Magneto-optical magnetic field/current sensors are based on the Faraday effect, which involves changing the polarized state of light. Polarimetric methods are therefore used for measuring polarization characteristics. Channeled polarimetry allows polarization information to be obtained from the analysis of the spectral domain.
View Article and Find Full Text PDFDual-Modal Approach for Ship Detection: Fusing Synthetic Aperture Radar and Optical Satellite Imagery.
Sensors (Basel)
January 2025
Department of Electrical and Software Engineering, University of Calgary, Calgary, AB T2N 1N4, Canada.
The fusion of synthetic aperture radar (SAR) and optical satellite imagery poses significant challenges for ship detection due to the distinct characteristics and noise profiles of each modality. Optical imagery provides high-resolution information but struggles in adverse weather and low-light conditions, reducing its reliability for maritime applications. In contrast, SAR imagery excels in these scenarios but is prone to noise and clutter, complicating vessel detection.
View Article and Find Full Text PDFA Review of the Impact of Sjögren's Syndrome and/or the Presence of Anti-Ro/SS-A Antibodies on Therapeutic Strategies for Rheumatoid Arthritis.
J Clin Med
January 2025
Department of Immunology and Rheumatology, Division of Advanced Preventive Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8523, Japan.
Rheumatoid arthritis (RA) is an immune-mediated disease characterized by polyarthritis that affects the small joints of the bilateral upper and lower extremities. RA shares several common clinical symptoms with Sjögren's syndrome (SS), another rheumatic disease caused by the lymphocytic infiltration of exocrine glands, with dry eye and dry mouth being the two most common symptoms. Anti-Ro/SS-A antibodies, a diagnostic biomarker of SS, are positive in patients with RA at a certain rate.
View Article and Find Full Text PDFWant 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!