检索结果-南通市图书馆

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Tungsten 2025年第1期7卷 152-160页

作者： Zhi-Jun Xie Jia-Lin Li Ling Gong Xiang-Li Zhong Hong-Jia Song Jin-Bin Wang National-Provincial laboratory of Special Function thin film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance

Performance enhancement of perovskite solar cells with Cs2PtI6-xBrx absorber layer based on numerical simulation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Optoelectronics Letters 2025年

作者： Du Zuyan Yuan Yujie Hou Guofu Xin Yupeng Bi Jinlian Li Wei Tianjin Key laboratory of film Electronic and Communication Devices， School of Integrated Circuit Science and Engineering， Tianjin University of Technology Institute of Photoelectronic thin film Devices and Technology， Nankai University

Cs2TiBr6， characterized as a lead-free vacancy-ordered double perovskite material， demonstrates notable stability and photoelectric performance， rendering it suitable for application in perovskite solar cells. However， the experimental efficiency of this material is currently limited， achieving only 3.12%. This efficiency limitation primarily stems from the material’s wide bandgap， which results in insufficient light absorption. To address this issue， this study utilized Cs2PtI6-xBrxfor band structure fine-tuning. By adjusting the bandgap of Cs2PtI6-xBrxthrough Br-doping， not only was the alignment of the energy bandgap in the absorption layer effectively adjusted， but the cutoff range of light absorption was also significantly expanded. Setting the Cs2PtI6-xBrxbandgap to 1.4 eV resulted in optimal device performance. Additionally， comparative analyses aimed at boosting solar cell efficiency were performed on both hole transport and electron transport layer materials. Subsequently， the structure of the perovskite solar cell was optimized using an FTO/TiO2/Cs2TiBr6/Cs2PtI6-xBrx/Cu2O/Au configuration. Furthermore， the influence of the absorber layer thickness and defect density on device performance was studied. Ultimately， this configuration enabled the Cs2TiBr6/Cs2PtI6-xBrxsolar cell to achieve a peak conversion efficiency of 29.69%.

关键词：

Eu@Sc_(20)C_(60):Magnetic Volleyballene

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2016年第10期33卷 149-152页

作者：赵荟艳马红曼王静刘英 Department of Physics and hebei advanced thin film laboratory Hebei Normal University

Recently, a stable hollow Sc20C60 cage with Th point group symmetry has been proposed, due to its volleyball- like shape called volleyballene. Here the structural and electronic properties for Sc20C60 cage with a europium atom are further studied based on density functional theory. The results give two stable low-lying Eu@Sc20C60 isomers, called cage-a and cage-b, respectively, which still retain the cage-like shape of Sc20C60 volleyballene. After a Eu atom is encaged into the Sc20C60 volleyballene, the HOMO-LUMO gaps decrease from 1.47eV of the Sc20C60 cage to 0.46 eV of cage-a and 0.21 eV of cage-b. Due to the half-filled 4f-electron orbital states of the Eu atom, the two low-lying Eu@Sc20C60 isomers have net magnetic moments of 7μB. This study further provides the possible applications for the Sc20C60 volleyballene, and enriches the species of magnetic cage-like molecules, which provides more information for magnetic storage and magnetic control.

关键词： Eu@Sc is for on cage Magnetic Volleyballene of

Achieving ultralow leakage current in Schottky-MIS cascode anode lateral field-effect diode based on AlGaN/GaN HEMT

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2025年第1期68卷 379-385页

作者： Fangzhou WANG Changhong GAO Guojian DING Cheng YU Zhuocheng WANG Xiaohui WANG Qi FENG Ping YU Peng ZUO Wanjun CHEN Yang WANG Haiqiang JIA Hong CHEN Bo ZHANG Zeheng WANG Songshan Lake Materials laboratory School of Microelectronics Southern University of Science and Technology State Key laboratory of Electronic thin films and Integrated Devices University of Electronic Science and Technology of China Manufacturing Commonwealth Scientific and Industrial Research Organisation

In this paper,we design and fabricate a Schottky-metal-insulator-semiconductor（MIS） cascode anode GaN lateral field-effect diode（CA-LFED） to achieve ultralow reverse leakage current(ILEAK).The device based on AlGaN/GaN highelectron-mobility-transistor（HEMT） includes a normally-off MIS-controlled channel that is cascoded with a high barrier height Schottky *** reverse bias,the high electric-field is effectively prevented by the normally-off MIS-controlled channel *** with the high barrier height Schottky contact,this feature significantly suppresses the *** by the device fabrication,the CA-LFED with high breakdown voltage（BV）>600 V shows an ultralow ILEAKof 3.6×10-9A/mm as well as a low forward voltage drop（VF） of 2.2 *** performance suggests that the CA-LFED can be a promising candidate for ultralow ILEAKand better VF-ILEAKtrade-off GaN power diode applications.

关键词： Schottky-MIS cascode anode lateral field-effect diode (LFED) ultralow reverse leakage current ($I_{\rm{LEAK}}$) forward drop and reverse leakage trade-off AlGaN/GaN HEMTs

同方期刊数据库

Transport properties in a multi-terminal regular polygonal quantum ring with Rashba spin-orbit coupling

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2012年第12期21卷 66-73页

作者：唐翰昭翟利学刘建军 Department of Physics and hebei advanced thin film laboratory Hebei Normal University Department of Physics Shijiazhuang University

Transport properties in a multi-terminal regular polygonal quantum ring with Rashba spin-orbit coupling （SOC） are investigated analytically using quantum networks and the transport matrix metLod. The results show that conduc- tances remain at exactly the same values when the output leads are located at axisymmetric positions. However, for the nonaxisymmetrical case, there is a phase difference between the upper and lower arm, which leads to zero conductances appearing periodically. An isotropy of the conductance is destroyed by the Rashba SOC effect in the axisymmetric case. In addition, the position of zero conductance is regulated with the strength of the Rashba SOC.

关键词： multi-terminal quantum ring Rashba spin-orbit coupling transport property

Wave-vector filtering effect of the electric-magnetic barrier in HgTe quantum wells

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2013年第3期22卷 466-470页

作者：邹永连宋俊涛 Institute of Physics Chinese Academy of Sciences Department of Physics and hebei advanced thin film laboratory Hebei Normal University

Because of the helicity of electrons in HgTe quantum wells（QWs） with inverted band structures,the electrons cannot be confined by electric barriers since electrons can tunnel the barriers perfectly without backscattering in the HgTe *** behavior is similar to Dirac electrons in *** this paper,we propose a scheme to confine carriers in HgTe QWs using an electric-magnetic *** calculate the transmission of carriers in 2-dimensional HgTe QWs and find that the wave-vector filtering effect of local magnetic fields can confine the *** confining effect will have a potential application in nanodevices based on HgTe QWs.

关键词： magnetic barrier topological insulator helical states HgTe quantum well

Structural and magnetic properties of La_(0.7)Sr_(0.1)Ag_xMnO_(3-δ) perovskite manganites

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2015年第5期24卷 546-552页

作者：侯雪纪登辉齐伟华唐贵德李壮志 hebei advanced thin film laboratory Department of Physics Hebei Normal University Department of Physics and Electronic Science Liupanshui Normal University

Ag-doped manganite powder samples, La0.7Sr0.1AgxMnO3 6 （x = 0.00, 0.025, 0.05, 0.075, and 0.10） were synthesized using the sol-gel method. X-ray diffraction patterns indicated that the samples had two phases with the R-3c perovskite being the dominant phase and Mn3O4 being the second phase. X-ray energy dispersive spectra indicated that the ratio of Ag to La was very close to that of the nominal composition in the samples. The specific saturation magnetizations at 300 K increased from 32.0 ***/kg when x = 0.00 to 46.8 A-mZ/kg when x = 0.10. The Curie temperature, TC, of the samples increased from 310 K when x = 0.00 to 328 K when x = 0.10. Because the atomic concentration ratios of La, Sr, and Mn in the five samples were all the same and only the Ag concentration changed, the variations of the specific saturation magnetizations at 300 K and the Curie temperatures suggested that the Ag cations have been doped into the A sites of the perovskite phase in the samples.

关键词： perovskite manganite Curie temperature cation vacancy crystal structure

Cation distributions estimated using the magnetic moments of the spinel ferrites Co_(1-x)Cr_xFe_2O_4 at 10K

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2014年第10期23卷 519-528页

作者：尚志丰齐伟华纪登辉徐静唐贵德张晓云李壮志郎莉莉 hebei advanced thin film laboratory Department of Physics Hebei Normal University Department of Physics and Electronic Science Liupanshui Normal University

（A）[B]2O4 ferrite samples with the composition COl_xCrxFe204 （0.0 ≤ x ≤1.0） are prepared using a hydrothermal method, and subjected to calcining in a tube furnace with an argon-flow at 1673 K for 2 h. X-ray diffraction patterns indicate that each of all the samples has a single phase cubic spinel structure with a space group of Fd3m. Magnetic measurements show that the saturation magnetization decreases with as the Cr content x increases. The cation distribution of the samples is estimated by fitting the dependence of the magnetic moments on x at l 0 K, using the quantum mechanical model previously proposed by our group. The calculated sum of the content values of the Cr3＋ and Cr2＋ cations occupying the （A） sites increases as the value of x increases. In the fitting process, the magnetic moment directions of the Cr3＋ and Cr2＋ cations are assumed to be antiparallel to those of the Fe and Co cations, respectively, which is in accordance with Hund＇s rules.

关键词： spinel ferrite magnetic property cation distribution ionicity

A reduction scheme of PAPR in CO-OFDM system using time-delay neural networks

在线全文

学校读者我要写书评

暂无评论

Optoelectronics Letters 2025年

作者： TONG Zhengrong LIU Zhihong WANG Hao ZHANG Weihua ZHANG Tianhao JIA Qiqi Tianjin Key laboratory of thin film Electronics and Communication Devices， Engineering Research Center for Optoelectronic Devices and Communication Technology of the Ministry of Education， School of Integrated Circuit Science and Engineering， Tianjin University of Technology

An iterative partial transmission sequence （IPTS） cascading time-delay neural network （TDNN） scheme is proposed to reduce peak-to-average power ratio （PAPR） in the coherent optical orthogonal frequency division multiplexing （CO-OFDM） systems. The IPTS algorithm further reduces computational complexity based on the partial transmission sequence （PTS） algorithm. TDNN is trained by the iterative clipping filtering （ICF） method. Simulation results show that the proposed scheme achieves a PAPR reduction of 5.84 dB when complementary cumulative distribution function （CCDF） is 10-4and an extra transmission distance of 200 km for 10-3bit error rate （BER） compared to the original signals.

关键词：