The 1S0-3P0 clock transition frequency nuSr in neutral 87Sr has been measured relative to the Cs standard by three independent laboratories in Boulder, Paris, and Tokyo over the last three years. The agreement on the 1 x 10(-15) level makes nuSr the best agreed-upon optical atomic frequency. We combine periodic variations in the 87Sr clock frequency with 199Hg+ and H-maser data to test local position invariance by obtaining the strongest limits to date on gravitational-coupling coefficients for the fine-structure constant alpha, electron-proton mass ratio mu, and light quark mass. Furthermore, after 199Hg+, 171Yb+, and H, we add 87Sr as the fourth optical atomic clock species to enhance constraints on yearly drifts of alpha and mu.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1103/PhysRevLett.100.140801 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Tetra-coordinated organoboron complexes with triaminoguanidine-salicylidene based ligands: aggregation induced enhanced emission and mechanoresponsive features.
Dalton Trans
January 2025
Department of Chemistry, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India.
Organoboron complexes have garnered significant attention due to their remarkable optical properties and diverse applications. However, synthesizing stable fused five-, six- and seven-membered organoboron complexes possess significant challenges. In this study, we successfully developed novel mono-nuclear (6-8 & 10) and di-nuclear (9) organoboron complexes supported by triaminoguanidine-salicylidene based -symmetric Schiff base ligands one-step condensation reaction with excess phenylboronic acid.
View Article and Find Full Text PDFAll-Fiber Multicomponent Gas Raman Probe Based on Platinum-Coated Capillary Enhanced Raman Spectroscopy.
ACS Sens
January 2025
National Engineering Research Center of Fiber Optic Sensing Technology and Networks, Wuhan University of Technology, Wuhan 430070, China.
This paper presents a compact all-fiber multicomponent gas Raman probe using a dual-fiber architecture within a platinum-coated capillary. The probe eliminates the need for conventional optical components like filters and dichroic mirrors by strategically employing metal coating on the excitation fiber's surface to suppress interference signals. A detailed analysis of the silica Raman signal and fluorescence propagation within the system facilitated this design.
View Article and Find Full Text PDFA Reliable High-Performance Floating-Gate Transistor Based on ZrS Native Oxidation for Optoelectronic Synergistic Artificial Synapses.
ACS Appl Mater Interfaces
January 2025
Henan Key Laboratory of Infrared Materials & Spectrum Measures and Applications, School of Physics, Henan Normal University, Xinxiang 453007, China.
Floating-gate transistors (FGTs), considered the most promising structure among three-terminal van der Waals (vdW) synaptic transistors, possess superiorities in improved data retention, excellent endurance properties, and multibit storage capacity, thereby overcoming the von Neumann bottleneck in conventional computing architectures. However, the dielectric layer in FGT devices typically depends on atomic layer deposition or mechanically transferred insulators, posing several challenges in terms of device compatibility, manufacturing complexity, and performance degradation. Therefore, it is crucial to discover dielectrics compatible with two-dimensional (2D) materials for further simplifying FGT structures and achieving optimal performance.
View Article and Find Full Text PDFTransformer-generated atomic embeddings to enhance prediction accuracy of crystal properties with machine learning.
Nat Commun
January 2025
School of Information Science and Technology, Fudan University, Shanghai, China.
Accelerating the discovery of novel crystal materials by machine learning is crucial for advancing various technologies from clean energy to information processing. The machine-learning models for prediction of materials properties require embedding atomic information, while traditional methods have limited effectiveness in enhancing prediction accuracy. Here, we proposed an atomic embedding strategy called universal atomic embeddings (UAEs) for their broad applicability as atomic fingerprints, and generated the UAE tensors based on the proposed CrystalTransformer model.
View Article and Find Full Text PDFSite-specific substitution in atomically precise carboranethiol-protected nanoclusters and concomitant changes in electronic properties.
Nat Commun
January 2025
DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE), Department of Chemistry, Indian Institute of Technology, Madras, Chennai, 600036, India.
We report the synthesis of [Ag(o-CBT)] abbreviated as Ag, a stable 8e⁻ anionic cluster with a unique Ag@Ag@Ag core-shell structure, where o-CBT is ortho-carborane-1-thiol. By substituting Ag atoms with Au and/or Cu at specific sites we created isostructural clusters [AuAg(o-CBT)] (AuAg), [AgCu(o-CBT)] (AgCu) and [AuAgCu(o-CBT)] (AuAgCu). These substitutions make systematic modulation of their structural and electronic properties.
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!