This article investigates the fundamental limitations of optical frequency transfer stability related to cost-effective implementation of signal transmission in duplex, unidirectional optical paths offered by a standard dense wavelength division multiplexing (DWDM) network. We pointed out the effect of a significant mismatch of phase fluctuations observed in pairs of fibers even when located in a common cable. We also measured the thermal sensitivities of individual DWDM optical modules in the context of the effectiveness of the signal stabilization system. Finally, we present the real implementation of the coherent optical carrier transfer in the operational DWDM network, showing the overall impact of all individual effects. We demonstrated that it is possible to obtain the long-term stability (one day averaging) within the range from 2 ×10 to 4 ×10 and typical frequency offset at the level of few times 10 in a 1500-km-long line by using the soil-deployed cables.
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http://dx.doi.org/10.1109/TUFFC.2019.2957176 | DOI Listing |
Nutr Res
December 2024
Faculty of Medicine Health and Life Science, Swansea University, Swansea, Wales, UK. Electronic address:
Limited research has examined the effect of meal composition on sleep. Based on previous research, we hypothesized that a low glycemic index (LGI) drink containing 50 g isomaltulose (Palatinose, GI = 32) would result in more N3 sleep, less rapid eye movement (REM) sleep, and better memory consolidation than a high glycemic index (HGI) drink containing 50 g glucose (GI = 100). Healthy males (n = 20) attended the laboratory on three occasions at least a week apart (one acclimatization night and two test nights).
View Article and Find Full Text PDFJ Phys Chem A
January 2025
Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.
We present direct frequency comb cavity ring-down spectroscopy with Vernier filtering as a straightforward approach to sensitive and multiplexed trace gas detection. The high finesse cavity acts both to extend the interaction length with the sample and as a spectral filter, alleviating the need for dispersive elements or an interferometer. In this demonstration, a free running interband cascade laser was used to generate a comb centered at 3.
View Article and Find Full Text PDFSci Adv
January 2025
Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China.
Artificial nanostructures with ultrafine and deep-subwavelength features have emerged as a paradigm-shifting platform to advanced light-field management, becoming key building blocks for high-performance integrated optoelectronics and flat optics. However, direct optical inspection of integrated chips remains a missing metrology gap that hinders quick feedback between design and fabrications. Here, we demonstrate that photothermal nonlinear scattering microscopy can be used for direct imaging and resolving of integrated optoelectronic chips beyond the diffraction limit.
View Article and Find Full Text PDFJ Biophotonics
January 2025
The College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin, China.
Diffuse optical tomography (DOT) enables the in vivo quantification of tissue chromophores, specifically the discernment of oxy- and deoxy-hemoglobin (HbO and HbR, correspondingly). This specific criterion is useful in detecting and predicting early-stage neoadjuvant breast cancer treatment response. To address the issues of the limited channels in the fiber-dependent breast DOT system and limited signal-to-noise ratio in the camera-dependent systems, we hereby present a camera-based lock-in detection scheme to achieve dynamic DOT with improved SNR, which adopted orthogonal frequency division multiplexing technology.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Sun Yat-Sen University, School of Chemistry and Chemical Engineering, 135 West Xingang Road, 510275, Guangzhou, CHINA.
Metal-organic complexes with long afterglow luminescence have attracted extensive attention due to potential applications in display, sensing and information security. However, most of the metal-organic complex long afterglow materials reported so far are limited to the use of UV light as the excitation source, and the ambiguity of the structure-activity relationship makes the development of metal-organic complexes extremely limited. Herein, a series of metal-organic complexes with ultralong emission lifetime is constructed by coordination assembly of Zn(II) with three isomers.
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