An asymmetric double semiconductor quantum well is proposed to realize two-dimensional parity-time (PT) symmetry and an electromagnetically induced grating. In such a nontrivial grating with PT symmetry, the incident probe photons can be diffracted to selected angles depending on the spatial relationship of the real and imaginary parts of the refractive index. Such results are due to the interference mechanism between the amplitude and phase of the grating and can be manipulated by the probe detuning, modulation amplitudes of the standing wave fields, and interaction length of the medium. Such a system may lead to new approaches of observing PT-symmetry-related phenomena and has potential applications in photoelectric devices requiring asymmetric light transport using semiconductor quantum wells.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1364/OE.26.032918 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Design of triplex-forming peptide nucleic acid-based fluorescent probes for forced intercalation sensing of double-stranded RNA structures.
Anal Sci
January 2025
Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-Ku, Sendai, 980-8578, Japan.
The diverse functional roles of RNA within cells have led to a growing interest in developing RNA-binding fluorescent probes to investigate RNA functions. In particular, the probes for double-stranded RNA (dsRNA) structures are of significant value given the importance of the secondary and tertiary RNA structures on their biologic functions. This review highlights our recent efforts on the development of triplex-forming peptide nucleic acid (TFP)-based probes for fluorescence sensing of dsRNA structures.
View Article and Find Full Text PDFMitotic chromatin marking governs the segregation of DNA damage.
Nat Commun
January 2025
Laboratory of Epigenome Integrity, Epigenetics & Cell Fate Centre, UMR7216 CNRS, Université Paris Cité, Paris, France.
The faithful segregation of intact genetic material and the perpetuation of chromatin states through mitotic cell divisions are pivotal for maintaining cell function and identity across cell generations. However, most exogenous mutagens generate long-lasting DNA lesions that are segregated during mitosis. How this segregation is controlled is unknown.
View Article and Find Full Text PDFPrecise Synthesis of Complex Si-Si Molecular Frameworks.
J Am Chem Soc
January 2025
Department of Chemistry, Johns Hopkins University, 3400 N. Charles St., Baltimore, Maryland 21218, United States.
In this Perspective, we highlight the emergence of target-oriented syntheses of complex molecules composed of Si-Si (oligosilanes) rather than C-C bonds. Saturated oligosilanes structurally resemble alkanes with respect to a tetrahedral geometry, a preference for a staggered conformation in linear chains, the ability to form stable small rings, and tetrahedral stereochemistry at asymmetrically functionalized Si centers. There are also critical differences, for example, differences in multiple bonding and the ability to form penta- and hexacoordinated structures, that mean that chemical reactivity and, in particular, rules for stereoselective synthesis do not cleanly translate from carbon to silicon.
View Article and Find Full Text PDFLarge-scale quantum photonic circuits require integrating multiple single-photon sources, which are typically based on spontaneous four-wave mixing (SFWM) in spiral waveguides or microring resonators (MRRs). Photons can be generated in both clockwise (CW) and counterclockwise (CCW) orientations from a single source in a Sagnac configuration, showing promise for improving scalability. In this work, we propose a fully integrable scheme for bidirectional creation and usage of single photons.
View Article and Find Full Text PDFWe develop fs laser-fabricated asymmetric couplers and zig-zag arrays consisting of single- and two-mode waveguides with bipartite Kerr nonlinearity in borosilicate (BK7) glass substrates. The fundamental mode ( orbital) is near resonance with the neighboring higher-order orbital, causing efficient light transfer at low power. Due to Kerr nonlinearity, the coupler works as an all-optical switch between and orbitals.
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!