A collection of static atoms is fixed in a crystal at a low temperature and prepared by a pulse of incident radiation of wave vector . The atoms are well described by an entangled Dicke-like state, in which each atom carries a characteristic phase factor exp(ik0.r(j)), where is the atomic position in the crystal. It is shown that a single photon absorbed by the N atoms will be followed by spontaneous emission in the same direction. Furthermore, phase matched emission is found when one photon is absorbed by N atoms followed by two-photon down-conversion.
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http://dx.doi.org/10.1103/PhysRevLett.96.010501 | DOI Listing |
Macromol Rapid Commun
January 2025
School of Chemistry and Chemical Engineering, Nantong University, Nantong, 226019, China.
A novel aggregation-induced emission (AIE)-based artificial light-harvesting system (LHS) is successfully assembled via the host-guest interaction of bis-naphthylacrylonitrile derivative (BND), water-soluble pillar[5]arene (WP5), and sulforhodamine 101 (SR101). After host-guest assembly, the formed WP5⊃BND complexes spontaneously self-aggregated into WP5⊃BND nanoparticles (donors) and SR101 (acceptors) is introduced into WP5⊃BND to fabricate WP5⊃BND-SR101 LHS. Through the investigation of energy transfer between donors and acceptors, the artificial light-harvesting processes are certified in WP5⊃BND-SR101 LHS and the absolute fluorescence quantum yields (Φ) are significantly improved from 8.
View Article and Find Full Text PDFPhys Rev Lett
December 2024
Department of Physics and Astronomy and Center for Fundamental Physics, Northwestern University, Evanston, Illinois 60208, USA.
We introduce a novel technique for enhancing the robustness of light-pulse atom interferometers against the pulse infidelities that typically limit their sensitivities. The technique uses quantum optimal control to favorably harness the multipath interference of the stray trajectories produced by imperfect atom-optics operations. We apply this method to a resonant atom interferometer and achieve thousandfold phase amplification, representing a 50-fold improvement over the performance observed without optimized control.
View Article and Find Full Text PDFJ Med Case Rep
December 2024
College of Medicine and Life Sciences, Division of Plastic and Reconstructive Surgery, University of Toledo, 3000 Arlington Ave, Toledo, OH, 43614, USA.
Background: Although rare, melanoma confined to the dermis or subcutaneous tissue without evidence of a primary cutaneous site should provoke consideration of melanoma of unknown primary. This diagnosis carries a favorable prognosis when compared with cutaneous metastatic melanoma. Several hypotheses have been proposed for how melanoma of unknown primary develops, two of which were considered in our patient case: (1) spontaneous regression of the primary tumor following metastasis or (2) the traumatic implantation of ectopic melanocytic cells in other tissues, such as the subcutaneous tissue.
View Article and Find Full Text PDFSci Rep
December 2024
Key Laboratory of Grain Information Processing and Control (Henan University of Technology), Ministry of Education, Zhengzhou, 450001, Henan, China.
The accurate and timely assessment of wheat freshness is not only a complex scientific endeavor but also a critical aspect of grain storage safety. This study introduces an innovative approach for evaluating wheat freshness by integrating machine learning algorithms with Biophoton Analytical Technology (BPAT). Initially, spontaneous ultraweak photon emissions from wheat are measured, and various statistical descriptors are derived to construct a feature vector.
View Article and Find Full Text PDFNat Commun
December 2024
School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, 710072, China.
Metastable supramolecular polymerization under kinetic control has recently been recognized as a closer way to biosystem than thermodynamic process. While impressive works on metastable supramolecular systems have been reported, the library of available non-covalent driving modes is still small and a simple yet versatile solution is highly desirable to design for easily regulating the energy landscapes of metastable aggregation. Herein, we propose a coopetition-driven metastability strategy for parallel/perpendicular aromatic stacking to construct metastable supramolecular polymers derived from a class of simple monomers consisting of lateral indoles and aromatic core.
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