检索结果-南通市图书馆

Dielectric properties of BST/MZO ceramic composites

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2009年第1期52卷 127-131页

作者： CUI JianDong WANG Yi DONG GuiXia DU Jun Advanced Electronic Materials Institute General Research Institute for Nonferrous MetalsBeijing 100088China

Ba0.6Sr0.4TiO3/Mg1-xZnxO (MZO, x = 0, 0.05, 0.10, 0.15 and 0.20) ceramic composites were prepared by traditional ceramic processing. The crystal structure, fracture surface morphology, and dielectric properties were investigated. The samples with x = 0, 0.05 and 0.10 exhibited favorable sintering behavior, and homogeneous diphase microstructure was obtained. Nevertheless, the microstructure of the samples with x = 0.15 and 0.20 was inhomogeneous and abnormal grain growth could be observed, and the abnormal grain growth induced the degradation of dielectric strength. The sample with x = 0.10 has relatively low dielectric loss (1.26×10-3) and the optimal FOM value (about 174).

关键词： tunability dielectric property composites BST

Multi-field coupled color-changing devices and structures

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2019年第6期62卷 1065-1066页

作者： BAO YinHua HAN Yu SONG WeiLi CHEN HaoSen FANG DaiNing State Key Laboratory for Turbulence and Complex System College of Engineering Peking University Beijing 100871 China Institute of Advanced Structure Technology Beijing Institute of Technology Beijing 100081 China

Multi-field coupling phenomenon plays a significant role in the design and fabrication of color-changing devices. By introducing external fields, such as strain/stress, electric, thermal, or chemical fields, these dev... 详细信息

关键词： Multi-field plays a significant optical tunability

Dielectric properties of BaMg_(1/3)Nb_(2/3)O_(3) doped Ba_(0.45)Sr_(0.55)TiO_(3) thin films for tunable microwave applications

在线全文

学校读者我要写书评

暂无评论

Journal of Advanced Dielectrics 2015年第4期5卷 21-29页

作者： Fikadu Alema Konstantin Pokhodnya Center for Nanoscale Science and Engineering North Dakota State University Fargo ND 58108USA Agnitron Technology Incorporated Eden Prairie MN 55344USA

Ba(Mg_(1/3)Nb_(2/3))O_(3)(BMN)doped and undoped B_(0.45)Sr_(0.55)TiO_(3)(BST)thin films were deposited via radio frequency magnetron sputtering on PUTiO_(2)/SiO_(2)/Al_(2)O_(3) *** surface morphology and chemical state analyses of the films have shown that the BMN doped BST film has a smoother surface with reduced oxygen vacancy,resulting in an improved insulating properties of the BST *** tunability,loss,and leakage current(LC)of the undoped and BMN doped BST thin flms were *** BMN dopant has remarkably reduced the dielectric loss(~38%)with no significant effect on the tunability of the BST film,leading to an increase in figure of merit(FOM).This is attributed to the opposing behavior of large Mg2+whose detrimental effect on tunability is partially compensated by small Nb5+as the two substitute Ti4+in the *** coupling between Mg″_(Ti)and V_(o)charged defects suppresses the dielectric loss in the film by cutting electrons from hopping between Ti *** LC of the films was investigated in the temperature range of 300-450K.A reduced LC measured for the BMN doped BST film was correlated to the formation of defect dipoles from Mg″_(Ti),V_(o)and Nb_(Ti) charged *** carrier transport properties of the films were analyzed in light of Schottky thermionic emission(SE)and Poole-Frenkel(PF)enmission *** result indicated that while the carrier transport mechanism in the undoped film is interface limited(SE),the conduction in the BMN doped film was dominated by bulk processes(PF).The change of the conduction mechanism from SE to PF as a result of BMN doping is atributed to the presence of uncoupled Nb_(Ti) stting as a positive trap center at the shallow donor level of the BST.

关键词： Barium strontium titanate sputtering frreletric thin film tunability leakage current permitivity loss figure of merit defect dipole

The dielectric studies on sol–gel routed molybdenum oxide thin film

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Advanced Dielectrics 2017年第2期7卷 21-27页

作者： P.Adal Arasu R.Victor Williams Department of Physics St.Joseph's CollegeTrichyIndia

The influence of temperature on the dielectric properties of sol-gel routed spin-coated molybdenum trioxide(MoO_(3)) thin film has been *** films were annealed at temperatures 250℃,350℃ and 400℃.The phase transformation from amorphous to-orthorhombic phase with preferential orientation(022)has been found by XRD for the film annealed above 250℃.The vibration modes of-orthorhombic MoO_(3) have been examined by Raman *** predominant Raman's band of-orthorhombic MoO_(3) thin film has been found at the frequency range 1000–600 cm^(-1).Using the UV–Vis spectrum,the band gap of the film is found to be 3.3–3.8 *** surface morphology of the MoO_(3) films has been examined by scanning electron *** AC conductivity measurement of the MoO_(3) film has been carried out in the frequency range 10–10^(6) *** frequency dependence of the impedance has been plotted in the complex *** variation of the capacitance and dielectric constant of MoO_(3) film with respect to temperature and frequency has been *** of capacitance and figure of merit of the film are also determined.

关键词： Sol-gel dielectric constant capacitance tunability Curie-temperature figure-of-merit

Tunable off-resonant Rydberg microwave frequency comb spectroscopy based on metawaveguide coupled Rydberg atoms

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Optics Letters 2024年第8期22卷 1-6页

作者： Lihua Zhang Zongkai Liu Bang Liu Qifeng Wang Yu Ma Tianyu Han Zhengyuan Zhang Hanchao Chen Shiyao Shao Qing Li Jun Zhang Dongsheng Ding Baosen Shi Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China

Studying Rydberg microwave frequency comb(MFC)spectroscopy helps increase the working bandwidth of the Rydberg *** Letter demonstrates off-resonant Rydberg MFC spectroscopy in a meta-waveguide-coupled Rydberg atomic *** off-resonant MFC field couples with the Rydberg atoms through a *** system can receive the microwave field in the working band from 0.5 GHz to 13.5 GHz,and the MFC spectroscopy covers a span of 36 MHz at three different arbitrarily-chosen frequencies of 2 GHz,3 GHz,and 5.8 *** MFC spectrum that covers a wide range of 125 MHz is also *** work is significant for tunable wide-band instant microwave signal detection in the Rydberg atomic system,which is useful in microwave frequency metrology,communication,and radar.

关键词： Rydberg atoms microwave frequency comb spectroscopy metawaveguide tunability

Continuous-wave and broadly tunable Cr:ZnSe laser pumped by a short wavelength Tm:YLF bulk laser

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Optics Letters 2024年第10期22卷 87-92页

作者： Milun Zhang Changwen Xu Yidan Wei Suliao Li Guoyang Liu Wenlong Li Dianyuan Fan International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060China Chengdu Dien Photoelectric Technology Co. Ltd.Chengdu 610199China

We demonstrate,for the first time and to the best of our knowledge,a continuous-wave and broadly tunable Cr:ZnSe bulk crystal laser pumped by a Tm:YLF bulk laser with 1845 nm and 1887 nm *** compare the output characteristics and wavelength-tuning properties of the continuous-wave operation at the two pump *** the continuous-wave operation,the maximum output power is 1.79 W with a slope efficiency of 28.8%,which is achieved at the pump wavelength of 1887 *** addition,a tuning range of~700 nm(696 nm)from 2040 nm to 2736 nm by using a reflective diffraction grating is *** the best of our knowledge,this is the widest tuning range realized so far for Cr:ZnSe bulk crystal tuned by gratings.

关键词： middle-infrared laser Cr:ZnSe solid-state laser continuous wave tunability

New Current Mode Lossy Integrator Employing CDDITA

在线全文

学校读者我要写书评

暂无评论

Circuits and Systems 2018年第8期9卷 117-123页

作者： Kuldeep Panwar Dinesh Prasad Mayank Srivastava Zainab Haseeb Department of Electronics and Communication Engineering Faculty of Engineering and Technology Jamia Millia Islamia New Delhi India Department of Electronics and Communication Engineering NIT Jamshedpur India

This work presents a novel current-mode (CM) lossless integrator that uses one current differencing differential input transconductance amplifier (CDDITA) and one grounded capacitor. The configuration based on single active element has several advantages from the aspect of monolithic integration, few are: reduced power consumption, chip miniaturization. Employment of grounded capacitor is also beneficial for monolithic integration. Specifying some of the key features of integrator proposed are: 1) purely resistorless, 2) electronically tunable, 3) current output available at the port having high impedance, and 4) excellent performance under non-ideal conditions. So, a resister-less current mode lossy integrator with electronic control employing single CDDITA has been proposed in this paper. The verification of workability of the proposed current mode integrator is well explained by the help of SPICE simulations using TSMC CMOS 0.18 μm technology node.

关键词： Current Differencing Differential Input Transconductance Amplifier Lossy Integrator Electronic tunability Grounded Capacitor

Diode-pumped, All-solid-state Cr∶LiSGaF Laser

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Lasers 2000年第5期 7-11页

作者： DAI Jianming ZHANG Lizhe ZHANG Weili CHAI Lu WANG Yong XING Qirong WANG Qingyue (Ultrafast Laser Laboratory, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Optoelectronic Information Science and Technolo

A compact and efficient CW Cr∶LiSGaF laser pumped by two 670 nm laser diodes was reported. Average power as high as 125 mW was generated with a absorbed pump power of 800 mW. The slope efficiency was 17.2%, and the threshold was 72 mW. The tunability of the laser in detail was investigated and a tuning range of 100 nm from 790 to 890 nm was obtained.

关键词： diode pumped Cr∶LiSGaF laser tunability

Low-Loss, Broadband and Tunable Negative Refractive Index Metamaterial

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Electromagnetic Analysis and Applications 2010年第2期2卷 104-110页

作者： Y.J. Huang G.J. Wen T.Q. Li K. Xie 不详

This paper report on a low-loss, broadband, and tunable negative refractive index metamaterial (NRIM) consisting of yttrium iron garnet (YIG) slabs and printed circuit boards (PCBs). The YIG slabs under an applied magnetic field provide a negative permeability and the PCBs provide a negative permittivity. The substrates of the PCBs decuple the interactions between the YIG slabs and wire array deposed on such substrates. The effective electromagnetic parameters of the NRIM and the conditions of exhibiting the negative refractive index character are analyzed theoretically. Then the negative transmission and negative refraction characters are investigated numerically and experimentally. The results indicate that the NRIM exhibits negative pass band within the X-band with a bandwidth of about 1 GHz and a peak transmission power of about - 2.5 dB. While changing the applied magnetic field from 2300 Oe to 2700 Oe, the measured pass band of NRIM shift from 8.42 GHz to 9.50 GHz with a 2.7 MHz/Oe step. The results open a sample way to fabricate the NRIM, further, the metamaterial cloak and absorber.

关键词： Metamaterial Negative Refractive Index tunability Low-Loss Broadband