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Spectral properties and energy transfer in YAlO_3 crystals doped with Ce ions and Mn ions

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Chinese Optics Letters 2010年第3期8卷 303-305页

作者：曹顿华赵广军董勤陈建玉程艳丁雨憧 Key Laboratory of Material Science and Technology for High Power Lasers Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

We report the luminescence properties and decay profiles of Ce：YAlO3, Mn：YAlO3, and Ce,Mn：YAlO3 crystals grown by Czochralski method. The spectroscopic properties show that both Mn2＋ ions and Mn4＋ ions exist in Mn：YA103 and Ce,Mn：YAlO3 crystals. The Mn2＋ ions have a broad emission band of 60 nm in Mn-doped YAlO3 crystal at 530 nm. The luminescence spectra also indicate that there is significant energy transfer between Ce3＋ and Mn4＋ in Ce,Mn：YA103 crystal. Because of the energy transfer, the first decay component in Ce,Mn：YAlO3 decreases from 24.5 to 10.8 ns, which is much faster than that of Ce：YAlO3.

关键词： Cerium Cerium compounds Crystals Energy transfer Ions Luminescence manganese compounds

Structural　and　Electrical　Properties　of　Barium　Strontium　Titanate　Thin　Film　on　Conductive　La1-χSrχMnO3　Bottom　Layer

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Chinese Physics Letters 2004年第6期21卷 1139-1142页

作者： MIAOJun CHENWei-Ran CHENBin YANGHao PENGWei ZHONGJian-Pin WUHao YUANJie XUBo QIUXiang-Gang CAOLi-Xin ZHAOBai-Ru NationalLaboratoryforSuperconductivity InstituteofPhySicsChineseAcademyofSciencesBeijing100080

Ferroelectrics and colossal magnetoresistance heterostructure Ba1−xSrxTiO3(BST)/La1−xSrxMnO3 (LSMO) have been fabricated on a LaAlO3 substrate by the pulse laser deposition method. The dielectric measurements show that at room temperature and 100kHz, the dielectric constant and loss tangent are about 990 and 0.012, respectively; the highest tunability is about 45% near 200K under the applied electric field of 200kV/cm. Further study indicates that the leakage current for the BST/LSMO heterostructure obeys the Schottky emission mechanism in the electric field region higher than 100kV/cm at room temperature.

关键词： manganese compounds

Magnetic and electric characteristics and abnormality of low-temperature resistivity in La_(0.67–x)Er_xSr_(0.33)MnO_3(0.00≤x≤0.20) system

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Journal of Rare Earths 2009年第5期27卷 834-838页

作者：刘宁严国清张明玉 Anhui Key Laboratory of Spin Electron and Nanomaterials Suzhou College College of Science Anhui Science and Technology University National Laboratory of Solid State Microstructures Physics DepartmentNanjing University

M-T curves, ρ-T curves, and MR-T curves of La0.67-xErxSr0.33MnO3(x=0.00, 0.10, 0.20) system were studied by experiments. The experiments showed that: with increasing the doping amount, the magnetic structure of the system transformed from long-range ferromagnetic ordering to spin-cluster glass state, and M-T curves bent up in the extremely low temperature range; the resistivity of the system increased with increasing doping amount and exhibited the minimum phenomenon of low-temperature resistivity. The variation of the magnetic and electric properties came from the extra magnetic coupling induced by the doping and from the Kondo effect induced by the lattice distortion and local magnetic moments which was similar to that induced by the scattering of magnetic impurities on electron spins. © 2009 The Chinese Society of Rare Earths.

关键词： Condensed matter physics Electric resistance Erbium Impurities Kondo effect Magnetic couplings Magnetic moments Magnetic structure manganese compounds Rare earths Solids Spin dynamics Spin glass

Effects of Magnetic Field on Charge—Ordering Transitions in La2CuO4.08 and Pr0.5Sr0.5Mno3

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Chinese Physics Letters 2003年第5期20卷 738-741页

作者： LIJian-Qi CHENLing YUHong-Chun Y.Matsui ZHAOZhong-Xian InstituteofPhysicsandCondensedMatterPhysics ChineseAcademyofSciencesBeijing100080 NationalInstituteforResearchinInorganicMaterials 1-1NamikiTsukubaIbaraki305Japan

The applied magnetic field can result in evident changes on the charge-ordering transitions in both Cu-based high Tc superconductors and Mn-based colossal magnetioresistance materials. Alternations of charge modulation and melting of well-defined charge stripes can be commonly observed when the magnetic field is over 2 T. We herein present the experimental data obtained in LaCuO4.08 and Pr0.5Sr0.5MnO3 materials, illustrating this kind of interesting phenomena at low temperatures. In particular, some essential structural features alternating along with charge-ordering transition have been discussed.

关键词： manganese compounds

Electrochemical properties of LiNi_(0.5)Mn_(1.3)Ti_(0.2)O_4/Li_4Ti_5O_(12)cells

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International Journal of Minerals,Metallurgy and Materials 2012年第5期19卷 457-460页

作者： Guo-qiang Liu Xi Wang Ya-jie Gao Lei Wen Guang-yin Liu Jian-jie Zheng Peng Cen Ying Li School of Materials and Metallurgy Northeastern University Shenyang 110004 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Spinel compounds LiNi0.5Mn1.3Ti0.2O4（LNMTO） and Li4Ti5O12 （LTO） were synthesized by different methods. The particle sizes of LNMTO and LTO are 0.5-2 and 0.5-0.8 μm, respectively. The LNMTO/LTO cell exhibits better electrochemical properties at both a low current rate of 0.2C and a high current rate of 1C. When the specific capacity was determined based on the mass of the LNMTO cathode, the LNMTO/LTO cell delivered 137 mA.h.g-1 at 0.2C and 118.2 mA-h-g-l at 1C, and the corresponding capacity retentions after 30 cycles are 88.5% and 92.4%, respectively.

关键词： lithium batteries titanium compounds nickel compounds manganese compounds oxides electrochemical properties

Colossal Magnetoresistive p—n Junctions of Te—Doped LaMnO3／Nb—doped SrTiO3

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Chinese Physics Letters 2003年第1期20卷 137-140页

作者：吕惠宾 LaboratoryofOpticalPhysics InstituteofPhysicsandCenterforCondensedMatterPhysicsChineseAcademyofScien

We have fabricated colossal magnetoresistive (CMR) p-n junctions made of Te-doped LaMnO3 and Nb-doped SrTiO3 with laser molecular beam epitaxy. The I-V characteristics of the La0.9Te0.1MnO3/SrNb0.01Ti0.99O3 p-n junctions as a function of applied magnetic field (0-5 T) were experimentally studied in the temperature range 77-300 K. The results indicate that the p-n junction exhibited the CMR behaviour. The magnetoresistance (MR) is positive at 220 K and 300 K, while it displays a negative MR at 77 K. For a positive bias, the MR ratios (ΔR/R0, ΔR = RH-R0) are 7.5% at 0.1 T and 18% at 5 T for 300 K, 5% at 0.1 T and 33% at 5 T for 220 K, -14% at 0.1 T and -71% at 5 T for 77 K. For a negative bias, the MR ratios are 6.3% at 0.1 T and 10.8% at 3 T for 300 K, 5.1% at 0.1 T and 15% at 3 T for 220 K, -19% at 0.1 T and -72% at 5 T for 77 K. The CMR behaviour of the p-n junction is different from those of the LaMnO3 compound family.

关键词： manganese compounds

Growth and characterization of high-quality Mn-doped LiAlO_2 single crystal

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Chinese Optics Letters 2010年第4期8卷 414-417页

作者：滕浩周圣明林辉贾婷婷侯肖瑞王军 Key Laboratory of Material Science and Technology for High Power Lasers Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

The growth of a Mn-doped LiAlO_2 single crystal by the Czochralski（CZ） method and the characterization of its spectroscopy and thermoluminescence（TL） are *** X-ray rocking curve and chemical etching analysis show that the as-grown crystal has good *** full-width at half-maximum （FWHM） of the LiAlO_2（200）ωrocking curve is 23.2 arcsec and the etching pits density of the（100） plane is（1.6-4.0）×10~4 cm^（-2）.The transmission spectrum indicates that the crystal is highly transparent in the 200-1500-nm wavelength *** emission spectrum of the crystal consists of a peak around 579 nm when excited with 428-nm *** TL spectra show that the LiAlO_2：Mn crystal has glow peaks at 150 and 172℃.The change of TL characteristics of the crystal before and after thermal annealing in the air is discussed,and the effect of annealing and irradiation on the evolution of defect types is analyzed.

关键词： Emission spectroscopy Etching Lithium alloys manganese compounds Single crystals Thermoluminescence

Giant Magnetoresistance Effect of the Nanoscale Layered—Perovskite La2.5—xK0.5＋xMn2O7（0〈x〈0.5）

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Chinese Physics Letters 2002年第6期19卷 857-860页

作者：钟伟张宁等 NationalLaboratoryofSolidStateMicrostructures NanjingUniversityNanjing210093 KeyLaboratoryofJiangsuProvinceforOpticandElectricTechniques NanjingNormalUniversityNanjing210024

Nanoscale layered-perovskite La2.5-xK0.5 + xMn2O7(0 详细信息

Nanoscale layered-perovskite La2.5-xK0.5 + xMn2O7(0manganese perovskites.

关键词： manganese compounds

Ti Anode with Ti-Mn Coating

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Rare Metals 1995年第3期14卷 189-192页

作者：何芬胡永海董俊卿北京有色金属研究总院北京

A new type anode, Ti anode with Ti-Mn coating, has been used to prepare EMD (Electrolytic manganese Dioxide) by some Chinese manufacturers for 4 years. The industry test shows that this anode has such characteristics as sturdy, light, fine mechanical performance, very high passivation resistance and corrosion resistance. The passivation of this anode is discussed and the results show that this anode is better than the pure titanium anode in the EMD industry.

关键词： Anodic polarization Coatings Electrolysis manganese compounds Titanium