Search

Your search keyword '"Zhao, Chengchun"' showing total 214 results
Start Over Author "Zhao, Chengchun"
214 results on '"Zhao, Chengchun"'

1. Thorium doped strontium fluoride crystal: a unique candidate for solid nuclear optical clock material

Author

Gong, Qiaorui, Li, Shanming, Zhang, Shulong, Tao, Siliang, Deng, Guoliang, Zhang, Peixiong, Zhao, Chengchun, Hang, Yin, Zhu, Shining, and Ma, Longsheng

Subjects
Condensed Matter - Materials Science, Physics - Optics
Abstract

We report a candidate with unique advantages in the cultivation of solid-state nuclear clock material, Th:SrF2 crystal. It not only has a segregation coefficient close to 1, which can achieve highly efficient and uniform doping of Th, but also ensures a high transmittance (~69% at 150 nm) while achieving extremely high doping concentration (232Th>6*10^20 cm^(-3). In addition, SrF2 crystal will not be irradiated-colored under strong {\alpha} radiation like CaF2 crystal, Th:SrF2 crystal is expected to fully unleash its high concentration doping characteristics while ensuring its transmission performance in nuclear transition band not be severely affected by 229Th radiation damage.

Published
2024

25. Multi-layer nanoarrays sandwiched by anodized aluminium oxide membranes: an approach to an inexpensive, reproducible, highly sensitive SERS substrate

Author

Zhao, Chengchun, Zhu, Yuan, Chen, Li, Zhou, Shaoxin, Su, Yuquan, Ji, Xu, Chen, Anqi, Gui, Xuchun, Tang, Zikang, and Liu, Zhaowei

Subjects
Nanotechnology, Bioengineering, Physical Sciences, Chemical Sciences, Technology, Nanoscience & Nanotechnology
Abstract

A large-scale sub-5 nm nanofabrication technique is developed based on double layer anodized aluminium oxide (AAO) porous membrane masking. This technique also provides a facile route to form multilayer nano-arrays (metal nanoarrays sandwiched by AAO membranes), which is very challenging for other techniques. Normally the AAO mask has to be sacrificed, yet in this work it is preserved as a part of the nanostructure. The preserved AAO layers as the support for the second/third layer of the metal arrays provide a high-refractive index background for the multilayer metal arrays. This background concentrates the local E-field more significantly and results in a much higher Surface-Enhanced Raman Spectroscopy (SERS) signal than single layer metal arrays. This technique may lead to the advent of an inexpensive, reproducible, highly sensitive SERS substrate. Moreover, the physical essence of the plasmonic enhancement is unveiled by finite element method based numerical simulations. Enhancements from the gaps and the multilayer nanostructure agree very well with the experiments. The calculated layer-by-layer electric field distribution determines the contribution from different layers and provides more insights into the 3D textured structure.

Published
2018

31. Growth, spectroscopy and laser operation of Tm,Ho:GdScO3 perovskite crystal

Author

Eremeev, Kirill, primary, Loiko, Pavel, additional, Zhao, Chengchun, additional, Lin, Zhang-Lang, additional, Mateos, Xavier, additional, Zin Elabedine, Ghassen, additional, Camy, Patrice, additional, Braud, Alain, additional, Griebner, Uwe, additional, Petrov, Valentin, additional, Zhang, Ge, additional, Li, Shanming, additional, Hang, Ying, additional, and Chen, Weidong, additional

Published
2024
Full Text
View/download PDF

33. SESAM mode-locked Yb:GdScO3 laser

Author

Química Física i Inorgànica, Universitat Rovira i Virgili, Guo, Jie; Li, Shanming; Zhao, Chengchun; Hang, Yin; Zeng, Huang-Jun; Lin, Zhang-Lang; Zhang, Ge; Elabedine, Ghassen Zin; Mateos, Xavier; Loiko, Pavel; Petrov, Valentin; Chen, Weidong; Liang, Xiaoyan, Química Física i Inorgànica, Universitat Rovira i Virgili, and Guo, Jie; Li, Shanming; Zhao, Chengchun; Hang, Yin; Zeng, Huang-Jun; Lin, Zhang-Lang; Zhang, Ge; Elabedine, Ghassen Zin; Mateos, Xavier; Loiko, Pavel; Petrov, Valentin; Chen, Weidong; Liang, Xiaoyan

Abstract

We report on the investigation of continuous -wave (CW) and SEmiconductor Saturable Absorber Mirror (SESAM) mode -locked operation of a Yb:GdScO3 laser. Using a single -transverse -mode, fiber -coupled InGaAs laser diode at 976 nm as a pump source, the Yb:GdScO3 laser delivers 343 mW output power at 1062 nm in the CW regime, which corresponds to a slope efficiency of 52%. Continuous tuning is possible across a wavelength range of 84 nm (1027-1111 nm). Using a commercial SESAM to initiate mode -locking and stabilize soliton-type pulse shaping, the Yb:GdScO3 laser produces pulses as short as 42 fs at 1065.9 nm, with an average output power of 40 mW at 66.89 MHz. To the best of our knowledge, this is the first demonstration of passively mode -locking with Yb:GdScO3 crystal.

Published
2024

35. Research Progress of Wide Bandgap Semiconductor ZnGa2O4.

Author

LEI Shasha, GONG Qiaorui, ZHAO Chengchun, SUN Xiaohui, and HANG Yin

Subjects
WIDE gap semiconductors, SEMICONDUCTOR materials, X-ray detection, THIN films, OPTOELECTRONIC devices, PHOTOELECTRICITY
Abstract

Due to their unique physical and chemical properties, wide bandgap semiconductor materials have shown great potential in the field of optoelectronic devices, and have received more and more research and attention. Zinc gallate (ZnGa2O4) is a wide bandgap semiconductor material, showing broad application prospects in the fields of solar-blind ultraviolet photoelectric detection and X-ray detection for its wide bandgap, unique structure and good thermal stability. In this paper, based on the basic structural characteristics of ZnGa2O4, the bandgap, photoelectric properties of ZnGa2 O4, the preparation methods of ZnGa2O4 bulk single crystal and thin film are introduced in detail. Combined with the recent research results of domestic and foreign scholars, the application prospects of ZnGa2 O4 in many fields are summarized, especially the research progress of solar-blind ultraviolet photoelectric detection, memristor, X-ray detection and power devices. Finally, the future development direction of ZnGa2O4 is prospected, and it is pointed out that the quality and performance of ZnGa2O4materials can be further improved to improve device performance and meet higher level application requirements. [ABSTRACT FROM AUTHOR]

Published
2024

45. Structures and Properties of High-Concentration Doped Th:CaF2Single Crystals for Solid-State Nuclear Clock Materials

Author

Gong, Qiaorui, Tao, Siliang, Zhao, Chengchun, Hang, Yin, Zhu, Shining, and Ma, Longsheng

Abstract

Thorium-doped vacuum ultraviolet (VUV) transparent crystals is a promising candidate for establishing a solid-state nuclear clock. Here, we report the research results on high-concentration doping of 232Th:CaF2single crystals. The structures, defects, and VUV transmittance performances of highly doped Th:CaF2crystals are investigated by theoretical and experimental methods. The defect configurations formed by Th and the charge compensation mechanism (Ca vacancy or interstitial F atoms) located at its first nearest neighbor position are mainly considered and studied. The preferred defect configuration is identified according to the doping concentration dependence of structural changes caused by the defects and the formation energies of the defects at different Ca or F chemical potentials. The cultivated Th:CaF2crystals maintain considerable high VUV transmittance levels while accommodating high doping concentrations, showcasing an exceptional comprehensive performance. The transmittances of 1-mm-thick samples with doping concentrations of 1.91 × 1020and 2.76 × 1020cm–3can reach ∼62% and 53% at 150 nm, respectively. The VUV transmittance exhibits a weak negative doping concentration dependence. The system factors that may cause distortion and additional deterioration of the VUV transmittance are discussed. Balancing and controlling the impacts of various factors will be of great significance for fully exploiting the advantages of Th:CaF2and other Th-doped crystals for a solid-state nuclear optical clock.

Published
2024
Full Text
View/download PDF

49. Selective Oxidation of Alkylarene in H2O Catalyzed by the Polyoxometalate Supported Chromium Catalyst.

Author

Zhao, Chengchun, Xie, Ya, Shi, Da, and Yu, Han

Subjects
*CHROMIUM catalysts, *CATALYST supports, *ACID derivatives, *CARBONYL compounds, *KETONIC acids, *AROMATIC aldehydes, *OXIDATION
Abstract

The selective oxidation of alkylarene is a quite straightforward and appealing way for production of aromatic aldehydes, ketones and aromatic acid derivatives. We synthesized Cr(III) catalyst, (NH4)3[CrMo6O18(OH)6], with reasonable activity towards selective oxidation of alkylarenes under mild conditions. The catalyst is supported by a central chromium mononucleus and a cyclic inorganic ligand composed of six MoVIO6 octahedra, avoiding the disadvantages of expensive and non‐recyclable organic ligand. It is efficient, green and can be recycled at least six times with high activity. At the same time, a wide range of substituted alkylarenes were found to be compatible, providing the corresponding carbonyl compounds in moderate‐to‐high yield. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results