低 温 物 理 学 报
(DIWEN WULI
XUEBAO)
第26卷 第4期 2004年11月
目 录
纳米ZrO2掺杂对烧结DyBaCuO块材微观结构及其超导电性的影响
………………………………………………………… 刘石香 付华明 徐克西 （273）
La0.95K0.05MnO3的低频内耗研究………………………王广涛 张敏平 万陵德 陈健 （280）
高温超导块脉冲磁化实验研究与理论模拟……霍海宽 丘明 夏东 徐哲 林良真 （288）
热处理温度对La4/3Sr5/3Mn2O7的结构及电输运性质的影响
………………………………………… 刘莉
牛乐园 张力江 夏正才 袁松柳 (295)
La2/3(Ca1-xMgx)1/3MnO3
(0≤x≤60%)系统中不寻常的超大磁电阻
…………………………………………… 牛乐园 刘莉 夏正才 刘胜 袁松柳 (300)
La4/3(Sr1-xBax)5/3Mn2O7的电输运性质研究…………………………………………………
…………………
张力江 刘莉 夏正才 张国宏 冯文 唐洁 刘胜 袁松柳 (304)
La2/3Ca1/3Mn1-x CuxO3(x =4%)中的热弛豫现象……………………张国宏 夏正才 袁松柳 (309)
HgBa2CuO4+δ中载流子分布的研究…………………………………刘文利 韩圣浩* 张酣 （314）
Al 和Sn离子掺杂对La1.2Ca1.8Mn2O7输运性质的影响
………………………………陈春霞 潘亚林 章建辉 钱天 周桃飞 李慧玲 （319）
MgB2电阻外场展宽的物理特性…………………………………韩永胜 杨宏新 陈曙 （325）
超薄单晶基底本征约瑟夫逊结的制备………………闫生超 尤立星 陈健 吴培亨 （330）
谐振子量子制冷循环………………………………………………何济洲 骆成洪 吴评 （334）
初探混合物理化学气相沉积法（HPCVD）制备不锈钢衬底MgB2超导厚膜样品
……… 王新峰 郭荆璞 贾璋 吕莹 朱萌 王晓楠 陈晋平 徐军 冯庆荣 (344)
多种优化方法及其在高温超导磁体优化设计中的应用
…………………………………………………………………………王超 王秋良 （350）
n型掺杂半导体In/Nb-SrTiO3金属异质结变温J～V特性的研究
……………………………………………………………刘大猛 连贵君 熊光成 （358）
CHINESE JOURNAL OF LOW TEMPERATURE PHYSICS
Vol.26 No.4 Nov., 2004
CONTENTS
Effect of Nano-ZrO2
Doping on Structure and Superconducting Properties of Sintered DyBaCuO
………………………………………………LIU SHI-XIANG, FU HUA-MING, XU KE-XI (279)
Low Frequency Internal Friction Study Of Phase Transition In La0.95K0.05MnO3
Bulk Materials
………………WANG GUANG-TAO， ZHANG
MIN-PING, WAN LING-DE, CHENG JIAN （287）
Experimental And Theoretic
Research On Pulse Field Magnetization Of Hts Bul
……………………HUO HAI-KUAN QIU MING XIA DONG XU ZHE LIN LIANG-ZHEN （294）
Effect of sintering temperature on the phase stability of La4/3Sr5/3Mn2O7
……………LIU LI, NIU LE-YUAN, ZHANG LI-JIANG, XIA ZHENG-CAI, YUAN SONG-LIU (299)
Anomalous Colossal
Magmetoresistance of La2/3(Ca1-xMgx)1/3MnO3 (0≤x≤60%) System
…………………NIU LE-YUAN, LIU LI, XIA ZHENG-CAI, LIU SHENG, YUAN SONG-LIU (303)
Study On The Electrical Transport Properties In Layered Manganites
La4/3(Sr1-xBax)5/3Mn2O7
System
……………………………ZHANG
LI-JIANG, LIU LI, XIA ZHENG-CAI, YUAN SONG-LIU
(308)
Thrmal
Hysteresis Of La2/3Ca1/3Mn1-xCuxO3(x=4%)
……………………………………………ZHANG GUO-HONG, XIA ZHENG-CAI, YUAN SONG-LIU (313)
Study
of carrier distribution and superconductivity in HgBa2CuO4+δ
……………………………………………………LIU WEN-LI， HAN SHENG-JIE， ZHANG HAN （318）
Effect of Al And Sn Substitution on The
Transport
Properties of Layered Perovskite Manganite La1.2Ca1.8Mn2O7
…CHEN CHUN-XIA, PAN YA-LIN,
ZHANG JIAN-HUI, QIAN
TIAN, ZHOU TAO-FEI, LI HUI-LIN (324)
Characteristics of resistance broadening in
applied fields of MgB2
………………………………………………………HAN YONG-SHENG, YANG HONG-XIN, CHEN SHU (329)
Fabrications
Of Intrinsic Josephson Junctions On Ultra Thin Single Crystals
………………………………………YAN SHENG-CHAO, YOU LI-XING, CHEN JIAN, WU PEI-HENG （333）
Quantum
Refrigeration Cycle Working with the Harmonic Oscillators
……………………………………………………………HE JI-ZHOU, LUO CHENG-HONG, WU PING (343)
Superconducting
Mgb2 Films Fabricated On Stainless Steel Substrate By Hybrid
Physical Chemical Vapor Deposition
……………………WANG
XIN-FENG, JIA ZHANG, GUO JING-PU,ZHU
MENG， LÜ YING，WANG
XIAO-NAN,
CHEN JIN-PIN G,
XU JUN， FENG QING-RONG (349)
Several
Optimal Design Methods and Their Applications in the Designs for HTS Magnets
………………………………………………………………………WANG CHAO， WANG QIU-LIANG (357)
The n-type
Metal-Semiconductor In/Nb-SrTiO3 Schottky Barrier Diodes
……………………………………………LIU DA-MENG， LIAN GUI-JUN， XIONG GUANG-CHENG （363）
纳米ZrO2掺杂对烧结DyBaCuO块材
微观结构及其超导电性的影响*
刘石香 付华明 徐克西
上海大学物理系,上海 200436
研究了纳米ZrO2掺杂及其掺杂浓度对烧结DyBa2Cu3Oy超导体的转变温度Tc和临界电流Ic在零磁场和磁场中的行为，在磁场中发现掺杂样品的临界电流密度明显高于纯DyBaCuO样品。这种磁场行为可能与掺杂样品粒子分布更加均匀，富纳米粒子区明显增加，从而形成有效钉扎中心有关。
关键词： 高温超导体，掺杂，钉扎中心，临界电流密度
PACC: 7470D; 7470S
Effect of Nano-ZrO2
Doping on
Structure and Superconducting
Properties of Sintered DyBaCuO
LIU SHI-XIANG,
FU HUA-MING, XU KE-XI
Physical Department, Shanghai University, Shanghai 200436
( Received 27 February, 2004; revised manuscript received 23 April, 2004
)
The effect of nano-ZrO2 doped in sintered
DyBa2Cu3Oy was studied. Experiments on R-T
curves and I-V characters of the studied samples show that doping with nano-ZrO2
particles is favorable for enhancement of critical current for the sample
under external magnetic field. Such a behavior seems to be resulted from
regularly distributed dislocations and substantial increasing in rich
nano-grain locations in the doped samples, which may act as effective pinning
centers.
Keywords: high temperature superconductors;
doping; pinning centers; critical current density
PACC:
7470D, 7470S
La0.95K0.05MnO3的低频内耗研究
王广涛 张敏平
万陵德 陈健
河南师范大学物理系信息与工程学院, 新乡 453002
本文研究了样品La0.95K0.05MnO3的内耗、直流电阻、交流磁化率.发现在20—275
K的温度范围内，在0.3T的磁场下有明显的磁阻（MR）效应，温度为259K时MR效应达到极大值26%.在直流电阻测量中发现267K时出现很尖锐的电阻峰；在220K附近出现“肩峰”.内耗温度曲线在210K—250K
的温度范围有一个很宽的内耗峰；在268K有一个很明显的内耗蜂同时伴随着模量软化，并且由Kissinger关系求出顺磁—铁磁转变的表观激活能Eap=0.53 eV.
关键词：内耗，巨磁阻，相分离
PACC:
6170L, 7530, 6480
Low frequency internal friction study of phase transition in La0.95K0.05MnO3
bulk materials
WANG GUANG-TAO， ZHANG MIN-PING, WAN LING-DE, CHENG JIAN
(Department of Physics, Henan Normal
University, Xinxiang 453002, China)
La0.95K0.05MnO3
has been studied by the internal friction, electrical resistance and AC
magnetic susceptibility. Large magnetoresistance (MR) exists in a wide
temperature range (20-275 K) in La0.95K0.05MnO3
specimen at low magnetic field (0.3T). A sharp peak (T=267K) and a shoulder
peak (T=220K) are observed in the R-T curve. Accompanied with the local minimum
of elastic modulus, the internal friction measurement reveals two peaks at
about 268K and 230K. The position
of the peaks in Q-1 do not shift with frequency, but their height of
the peaks in Q-1 decrease with frequency increasing, which are general
characters of the low frequency internal friction associated with the phase
transition. The apparent activation energy of the phase transition Eap was obtained as 0.53eV.
From above experiments we draw the conclusion that there exists the phase
separation in the sample.
Keywords: internal friction, magnetoresistance, phase separation
PACC: 6170L, 7530, 6480
高温超导块脉冲磁化实验研究与理论模拟
霍海宽 丘明 夏东 徐哲 林良真
中科院电工研究所，北京 100080
通过磁化熔融织构超导块材俘获远高于常规永磁体的磁场，可以用于磁分离、制作电机等，如何磁化是其中关键技术问题之一。脉冲磁化目前被认为是最有前景的超导块材的磁化方式之一。我们通过霍尔元件测量脉冲磁化过程中超导块材表面磁场的变化，并运用磁通蠕动流动模型和幂指数模型分别描述脉冲磁化过程，理论与实验相比较，结果表明磁通蠕动流动模型能够更好地描述脉冲磁化，热量的产生、局域的温升直接关系到俘获磁场的大小，通过合理的铁轭设置和利用多脉冲磁化技术有助于提高最终的磁化效果。
关键词：超导块材，脉冲磁化，热量，数字模拟
PACC: 0720; 0630L
EXPERIMENTAL
AND THEORETIC RESEARCH ON PULSE FIELD MAGNETIZATION OF HTS BULK
HUO HAI-KUAN QIU MING XIA DONG XU ZHE LIN LIANG-ZHEN
Institute of
Electrical Engineering, Chinese Academy of Science, Beijing 100080
The trapped field
of HTS bulk is higher than that of the conventional magnetic material at low
temperature, so we can use this bulk to design the electrical motor. In
practice the magnetization of HTS bulk is the key problem and the pulse field
magnetization is considered to be one of the most useful methods. The
magnetization process is simulated by using the flux flow-creep model and power
law model, respectively. The experiment is also carried out to measure the
magnetic field through three Hall sensors mounted in the surface of HTS bulk.
It seems that the flux flow-creep model is better than power law model in
describing the pulsed field magnetization. Through further analysis we get that
the use of ferrite yoke and multi-pulse technical can improve the result of
pulse magnetization.
Keywords: Bulk HTS, pulsed field
magnetization, heat generation, numerical simulation
PACC: 0720; 0630L
热处理温度对La4/3Sr5/3Mn2O7的结构
及电输运性质的影响
刘莉 牛乐园 张力江 夏正才 袁松柳
华中科技大学物理系，武汉，430074
用溶胶-凝胶法并经过不同温度(TA)处理而制备出La4/3Sr5/3Mn2O7多晶样品。零场下阻温关系测量表明，较低TA处理的样品有较高的绝缘体-金属转变温度TP，而对较高TA处理的样品，其TP在表面和体内有较大差别，表面上有较高的TP值，且电阻率较低，但在体内TP低且电阻率高。结合结构分析，我们认为，较高温度处理有利于Sr3Ti2O7相的形成，但太高温度（如高于1450oC）处理的样品，虽然以Sr3Ti2O7相为主，但其表面易形成(La,Sr)MnO3相。
关键词：双层钙钛矿锰基氧化物 退火温度 X射线衍射 绝缘体-金属转变 磁电阻
PACC： 8140E，7130，7530V，1240P
Effect of sintering temperature
on the phase stability of La4/3Sr5/3Mn2O7
LIU LI
NIU LE-YUAN ZHANG LI-JIANG XIA ZHENG-CAI
YUAN SONG-LIU
Department of Physics, Huazhong, University of Science and
Technology, Wuhan 430074
（ Received 25 October, 2003）
La4/3Sr5/3Mn2O7
bulk samples are prepared under various anneal temperatures (TA) by sol-gel. Electric
transport measurements with no magnetic field show that the insulator-metal
transition temperature Tp is
higher in the sample annealed at lower temperatures. For the samples annealed
at higher temperatures, on the surface the Tp
is higher and the resistivity is smaller, but in the bulk the Tp is lower and the resistivity is
larger. With the structure analysis, we considered that higher anneal
temperatures are propitious to the form of Sr3Ti2O7
phase. However for the sample annealed at too high temperatures, although it’s
main phase is Sr3Ti2O7 phase, its surface is
likely to be (La,Sr)MnO3 phase.
Keywords：layered
maganites, X-ray diffraction ,
insulator-metal
transition magnetoresistance
PACC： 8140E，7130，7530V，1240P
La2/3(Ca1-xMgx)1/3MnO3 (0≤x≤60%)系统
中不寻常的超大磁电阻
牛乐园 刘莉 夏正才 刘胜 袁松柳
华中科技大学 武汉430074
用溶胶-凝胶法并经过1450℃后处理而制备出名义组分为La2/3(Ca1-xMgx)1/3MnO3 (0≤x≤60%)多晶样品。磁化测量表明，除磁转变温度因Mg掺杂而稍有降低外，磁性质整体上和不含Mg样品无本质上的差别。未加磁场下阻温关系测量表明，即使Mg含量高达60%，实验上仍观察到绝缘体到金属的转变。特别有意义的结果是，适当的Mg掺杂可明显提高转变温度附近的磁电阻效应，例如，在Mg掺杂量为30～40%的样品中，1T磁场下观察到的磁电阻甚至比不含Mg样品在5T磁场下得到的值还要大。
关键词：绝缘体-金属转变 , 磁电阻，磁化强度
PACC： 7130, 7530V, 7560E
ANOMALOUS COLOSSAL MAGMETORESISTANCE OF
La2/3(Ca1-xMgx)1/3MnO3 (0≤x≤60%) SYSTEM
NIU LE-YUAN
LIU LI XIA ZHENG-CAI LIU SHENG YUAN SONG-LIU
Department of
Physics, Huazhong,
University of Science and Technology,Wuhan 430074
( Received 23 October,2003)
La2/3(Ca1-xMgx)1/3MnO3
samples were prepared by sol-gel method and sintered at 1450°C for 12 hours. Magnetization measurements indicate
that the insulator-metal transition temperature Tp goes down gradually with the increase of Mg content, but the
magnetism property has no essential difference compared with the sample without
Mg . Electric transport measurements indicate that even Mg content reaches 60%, the
insulator-metal transition is still observable. The most interesting result is
that , the CMR around Tp can be markedly
enhanced by substituting appropriate Mg ion for Ca ion. For example, the sample substituted Mg with
30 to 40 percent in 1T magnetic field has
bigger CMR than the sample without Mg even in 5T magnetic field.
Keywords: insulator-metal
transition,
magnetoresistance,
magnetization
PACC: 7130, 7530V, 7560E