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941.
942.
943.
944.
Simulation of dielectric resonator for a high-T_c radio frequency superconducting quantum interference device 下载免费PDF全文
Nowadays,the high-critical-temperature radio frequency superconducting quantum interference device (high-T c rf SQUID) is usually coupled to a dielectric resonator that is a standard 10 × 10 × 1 mm 3 SrTiO 3 (STO) substrate with a YBa 2 Cu 3 O 7-δ (YBCO) thin-film flux focuser deposited on it.Recently,we have simulated a dielectric resonator for the high-T c rf SQUID by using the ANSOFT High Frequency Structure Simulator (ANSOFT HFSS).We simulate the resonant frequency and the quality factor of our dielectric resonator when it is unloaded or matches a 50-impedance.The simulation results are quite close to the practical measurements.Our study shows that ANSOFT HFSS is quite suitable for simulating the dielectric resonator used for the high-T c rf SQUID.Therefore,we think the ANSOFT HFSS can be very helpful for investigating the characteristics of dielectric resonators for high-T c rf SQUIDs. 相似文献
945.
Bo ZhuChun-Mei Liu Ming-Bang LvXiang-Rong Chen Jun Zhu Guang-Fu Ji 《Physica B: Condensed Matter》2011,406(18):3508-3513
We investigate the structural, phase transition and elastic properties of SnO2 in the rutile-type, pyrite-type, ZrO2-type and cotunnite-type phases by the plane-wave pseudopotential density functional theory method. The lattice constants, bulk modulus and its pressure derivative are well consistent with the available experimental and other theoretical data. Also, we find that the rutile→pyrite, pyrite→ZrO2 and ZrO2→cotunnite phase transition occur at 12.9, 59.1 and 111.1 GPa, which are in better agreement with the experimental results than those of Gracia et al. (2007). Moreover, we obtain the pressure dependences of elastic constants for the four structures. 相似文献
946.
Jia-Jin Tan Guang-Fu Ji Xiang-Rong Chen Zhe Li 《Physica B: Condensed Matter》2011,406(15-16):2925-2930
We have performed theoretical investigations on the structure, equation of state (EOS), elasticity, and mechanical properties of 2, 4, 6, 8, 10, 12-Hexanitrohexaazaisowurzitane (HNIW) energetic material by molecular dynamics (MD) simulations. The lattice parameters and equations of state of the four polymorphs (ε-, γ-, β-, and α-HNIW) under high pressure are calculated. Our calculated results agree with the previous experiments and theoretical calculations. Meanwhile, the elastic constants and some other mechanical properties of the most stable ε-HNIW under high pressure and temperature are predicted successfully. 相似文献
947.
948.
This paper gives the general expressions for the compliance s′ijkl, Young's modulus E(hkl) and Poisson's ratio v(hkl, θ) along arbitrary loading direction [hkl] for tetragonal crystals. The representation surface for which the length of the radius vector in the [hkl] direction equals E(hkl) and representation curve for which the length of the radius vector with angle θ deviated from the reference directions [001^-], [100], [001^-], [101^-] and [112^-] equals v(100, θ), v(001, θ), v(110,θ), v(101,θ) and v(111, θ) respectively, are constructed for nine tetragonal crystals (ammonium dihydrogen arsenate, ammonium dihydrogen phosphate, barium titanate, indium, nickel sulfate, potassium dihydrogen arsenate, potassium dihydrogen phosphate, tin and zircon). The characteristics of them are analysed in detail. 相似文献
949.
Plasma doping is the candidate for semiconductor doping. Accurate simulation of the doping technology is needed for the advanced integrated circuit manufacturing. In this paper, the plasma doping process simulation is performed by using the localized molecular dynamics method. Models that involve the statistics of the implanted compositions, angles and energies are developed. The effect of the model on simulation results is studied. The simulation results about the doping concentration profile are supported by experimental data. 相似文献
950.
Shen Ting-gen Zhou Yue-qun Ge Jun Yu Feng-chao Ji Pei-lai Wang Gang 《Journal of Russian Laser Research》2008,29(3):255-261
The method of finite-difference-time domain (FDTD) was used to study the characteristics of the patch antenna based on drilling
air holes in the PBG substrate. The results obtained show that the waves propagating along the substrate surface can be suppressed
by the drilled photonic crystal band gap (PBG) structure due to the influence of its forbidden band. The energy of the electromagnetic
waves is concentrated mainly in the substrate. As a result, patch antennas based on drilling air holes in the PBG substrate
have lower return losses (S11) in comparison with the conventional patch antennas; thus, a high gain is reached and the performance
is improved. Due to such the advantages, the use of patch antennas can be extended to such fields as mobile communication,
satellite communication, aviation, etc. 相似文献