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1.
Superconducting La1.937Sr0.063CuO4 crystals grown by the travelling-solvent floating-zone technique were thermally treated under various temperatures and oxygen pressures for moderately adjusting the oxygen content. The response of intrinsic electronic property of the crystals to the change of hole density in La2-xSrxCuO4 in the vicinity of the magic doping of x= 1/16 (= 0.0625) is studied in detail by magnetic measurements under various fields up to 1 T. It is found that when the superconducting critical temperature (Tc) increases with the oxygen content, there appears also a new subtle electronic state that can be detected from the differential curves of diamagnetic susceptibility dx/dT of the crystal sample. In contrast with the intrinsic state, the new subtle electronic state is very fragile under the magnetic fields. Our results indicate that a moderate change in oxygen doping does not significantly modify the intrinsic electronic state originally existing at the magic doping level. 相似文献
2.
The effects of interstitial oxygen on superconducting electronic phases in strontium and oxygen co-doped La1.937Sr0.063CuO4+δ
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Strontium and oxygen co-doped La1.937Sr0.063CuO4+δ superconductor with Tc≈ 40K, which is obtained by oxidizing strontium-doped starting ceramic sample La1.937Sr0.063CuO4 in NaC10 solution, is annealed under different conditions to allow interstitial oxygen to redistribute. The evolution of the intrinsic superconducting property with the oxygen redistribution is studied in detail by magnetic measurements in various fields. It is found that there occurs the electronic phase separation from the single superconducting phase with Tc ≈ 40 K into two coexisting superconducting states with values of Tc: 15 and 40K or of 15 and 35 K in this system, depending on annealing condition. Our results indicate that the 15, 35 and 40 K superconducting phases associated with the excess oxygen redistribution are all thermodynamically meta-stable intrinsic states in this Sr/O co-doped cuprate. 相似文献
3.
Effect of Fe3O4 segregation at grain boundaries on the electrical transport and magnetic properties of La0.67Ca0.33MnO3 is investigated. The experimental results show that the Fe3O4 segregation not only shifts the paramagnetic-ferromagnetic transition temperature of La0.6TCa0.33MnO3 to a lower temperature region but also induces a new transition in a lower temperature region. Meanwhile, the transition processes observed in both the resistivity and magnetization curves are obviously widened. Compared to pure La0.67Ca0.33MnO3, we assume that the Fe3O4 segregation level at the grain boundaries can modify the electrical transport and magnetic properties of La0.67Ca0.33MnO3. 相似文献
4.
Turbulence-induced changes in degree of polarization, degree of coherence and spectrum of partially coherent electromagnetic beams
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Based on a recently formulated unified theory of coherence
and polarization, a method is described to study turbulence-induced
changes in the polarization, the coherence and the spectrum of
partially coherent electromagnetic beams on propagation. The
electromagnetic Gaussian Schell-model beam is taken as a typical
example of partially coherent electromagnetic beams, and the
closed-form expressions for the degree of polarization, the degree
of coherence and the spectrum of electromagnetic Gaussian
Schell-model beams propagating through atmospheric turbulence are
derived in the quadratic approximation of Rytov's phase structure
function. Some interesting results are obtained, which are
illustrated by numerical examples and are explained in physics. 相似文献
5.
张文号 孙袆 张金松 李坊森 郭明华 赵弇斐 张慧敏 彭俊平 邢颖 王慧超 FUJITA Takeshi HIRATA Akihiko 李志 丁浩 汤辰佳 王萌 王庆艳 何珂 季帅华 陈曦 王俊峰 夏正才 李亮 王亚愚 王健 王立莉 陈明伟 薛其坤 马旭村 《中国物理快报》2014,(1):156-160
We prepared one-unit-ceil (1-UC) thick FeSe films on insulating SrTiOa substrates with non-superconducting FeTe protection layers by molecular beam epitaxy for ex situ studies. By direct transport and magnetic measurements, we provide definitive evidence for high temperature superconductivity in the 1-UC FeSe films with an onset Tc above 40 K and an extremely large critical current density fie Jc-1.7× 106 A/cm2 at 2K, which are much higher than Tc-8K and Jc-104 A/cm^2 for bulk FeSe, respectively. Our work may pave the way to enhancing and tailoring superconductivity by interface engineering. 相似文献
6.
在自行研发的0.8 μm SOI工艺平台上开发了基于SOI技术的单层多晶硅EEPROM(electrically erasable programmable read only memory)和SONOS (silicon-oxide-nitride-oxide-silicon)EEPROM,并进行了抗总剂量辐照实验研究,分析了各种EEPROM结构在抗总剂量辐照下的失效机理.结果表明基于SOI 技术的SONOS EEPROM具有良好的抗总剂量辐照性能,为抗辐照EEPROM电路中的存储单元结构选取提供了依据.
关键词:
EEPROM
SOI SONOS
辐照
浮栅 相似文献
7.
Yao-Wen Mao Cheng-Cheng Zhang Rui-Long Wang Hai-Bo Xiao Ling-Fang Xu Zheng-Cai Xia Chang-Ping Yang 《The European Physical Journal B - Condensed Matter and Complex Systems》2018,91(10):261
Two successive magnetocaloric effects consisting of inverse magnetocaloric effect around martensitic transition and negative magnetocaloric effect around magnetic transition of austenitic phase have been observed in Ni50Mn34In15Al alloy. Large inverse magnetic entropy change ΔSm ( ~ 21.3 J kg?1 K?1), small thermal and magnetic hysteresis of martensitic transition give rise of large net refrigerant capacity ( ~ 152.3 J kg?1) under a magnetic field of 50 kOe, which is comparable with that ( ~ 157.9 J kg?1) of second-order transition. The large combined magnetocaloric effects make the Ni50Mn34In15Al alloy as a promising candidate material for room temperature magnetic refrigeration. 相似文献
8.
本文运用第一性原理的计算方法, 以C/TM和N/TM共掺杂(碳与过渡金属共掺杂和氮与过渡金属共掺杂)TiO2为例, 分别计算了它们共掺杂TiO2的束缚能、能带结构和态密度等, 通过对双掺杂结构的束缚能计算, 发现非金属和金属杂质有团聚成键的趋势, 其正的束缚能说明了掺杂原子与周围的原子成键, 因成键作用减少的体系能量高于因几何畸变带来的应力能. 在对N/V和C/Cr共掺杂能带结构和分子成键的详细分析中, 发现非金属和金属共掺杂TiO2, 要使掺杂后TiO2的光吸收边红移较大, 光催化性能较好, 就要符合金属和非金属共掺杂协同机制, 即 掺杂后在导带底下方和价带顶上方分别出现由金属3d和非金属2p态提供的杂质能级. 相似文献
9.
Shou-Xin Wang Jie Huang Zhi-Jin Fan Huan Wang Yi-Feng Fu Na Mi Zheng-Cai Zhang Hai-Bin Song Nataliya P. Belskaya Vasiliy A. Bakulev 《Journal of chemical crystallography》2011,41(9):1348-1354
Abstract
The title compounds, quinolin-8-yl 4-methyl-1,2,3-thiadiazole-5-carboxylate 2a and 2-nitrophenyl 4-methyl-1,2,3-thiadiazole-5-carboxylate 2b, synthesized by the reaction of 4-methyl-1,2,3-thiadiazole-5-carbonyl chloride with 8-hydroxyquinoline and 2-nitrophenol, were confirmed by single-crystal X-ray diffraction [CCDC 783328 and 784970]. The 2a crystallizes in triclinic space group P-1 with cell parameters a = 7.957(7) ?, b = 8.378(7) ?, c = 10.097(10) ?, α = 100.63(2)°, β = 112.742(17)°, γ = 93.287(4)° and Z = 2. The 2b crystallizes in triclinic space group P-1 with cell parameters a = 7.134(4) ?, b = 8.154(4) ?, c = 10.254(5) ?, α = 99.501(9)°, β = 91.311(7)°, γ = 109.518(8)° and Z = 2. Packing in the compound 2a is dominated by weak C–H···N and C–H···O hydrogen bonds. In the compound 2b, molecules are linked through intermolecular C–H···O hydrogen bonds interactions. The preliminary bioassay showed that the title compound 2a had excellent antifungal activity with the EC50 detected as from 2.99 to 28.35 μg/mL and the EC90 detected as from 21.041 to 175.17 μg/mL. Both of the title compounds 2a and 2b had good inhibition activity of tobacco mosaic virus (TMV) and good induction activity of tobacco against TMV with potential systemic acquired resistance. 相似文献10.
REN Zhi-An LU Wei YANG Jie YI Wei SHEN Xiao-Li LI Zheng-Cai CHE Guang-Can DONG Xiao-Li SUN Li-Ling ZHOU Fang ZHAO Zhong-Xian 《中国物理快报》2008,25(6):2215-2216
We report the superconductivity in iron-based oxyarsenide Sm[O1-xFx]FeAs, with the onset resistivity transition temperature at 55.0K and Meissner transition at 54.6K. This compound has the same crystal structure as LaOFeAs with shrunk crystal lattices, and becomes the superconductor with the highest critical temperature among all materials besides copper oxides up to now. 相似文献