[1]卢天倪,孙昱艳,齐铭,等.利用第一性原理计算分析Bi-2212超导机理及H2S零电阻现象的成因[J].中国材料进展,2017,(5):016-20.[doi:10.7502/j.issn.1674-3962.2017.05.04]
 LU Tianni,SUN Yuyan,QI Ming,et al.The Analysis of the Bi-2212 Superconducting Mechanism and the reason of H2S Zero-Resistance Phenomenon by First Principle Calculations[J].MATERIALS CHINA,2017,(5):016-20.[doi:10.7502/j.issn.1674-3962.2017.05.04]
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利用第一性原理计算分析Bi-2212超导机理及H2S零电阻现象的成因()
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中国材料进展[ISSN:1674-3962/CN:61-1473/TG]

卷:
期数:
2017年第5期
页码:
016-20
栏目:
前沿综述
出版日期:
2017-05-31

文章信息/Info

Title:
The Analysis of the Bi-2212 Superconducting Mechanism and the reason of H2S Zero-Resistance Phenomenon by First Principle Calculations
作者:
卢天倪孙昱艳齐铭周廉
西安交通大学材料金属材料强度国家重点实验室, 西北有色金属研究院超导材料研究所, 西安建筑科技大学,西安航空学院
Author(s):
LU Tianni SUN Yuyan QI Ming ZHOU Lian
State key Laboratory for Mechanical behavior of Materials, Xi’an Jiaotong Unversity; SMRC, Northwest Institute for Nonferrous Metal Research; Xi’an University of Architecture and Technology; Xi’an Aeronautical University
关键词:
H2SBi-2212掺杂分波态密度谱电子团聚第一性原理计算
Keywords:
H2S Bi-2212 doping Partial density of states Electronic reunion First principle calculation
DOI:
10.7502/j.issn.1674-3962.2017.05.04
文献标志码:
A
摘要:
本文利用第一性原理分别对掺杂的Bi-2212高温超导材料以及高压下的H2S分子中各元素的分波态密度谱(PDOS)进行了计算。根据计算结果对Bi-2212的超导转变温度Tc随掺杂含量改变而变化以及H2S在高压下的零电阻现象进行了分析。在Bi-2212超导材料处于最佳掺杂含量时,电子能量接近于费米面附近的超导赝能隙从而降低了形成超导电子对所需的凝聚能,因此这些电子转变为超导电子对。另外,靠近费米面处的电子态密度在最佳掺杂量时达到最大值,即能够被诱导为库伯对的电子数量增多,在上述两方面的共同作用下,电子在较高的温度下能够更容易转变为超导电子对,因此超导转变温度提高。本文还对高压下的H2S晶体的PDOS谱进行了计算,根据计算的结果,高压下的H2S由于晶格的收缩破坏了原子之间的成键,使得电子的分布已经不满足泡利不相容原理,而是以一种类似于“团聚”的形式存在。当对高压下的H2S加载电压后,这些“团聚”的电子能够作为载流子移动从而形成电流,在此过程中,电子之间很难发生碰撞,其总动量的改变量可以认为是零,这是造成高压下的H2S能够在室温范围内表现出“零电阻”现象的成因。
Abstract:
In this paper, the Partial Density of States (PDOS) of each element in doped Bi-2212 high temperature superconductor and H2S under high pressure is calculated by the first principle. According to the calculation results, we analysis the phenomenon that the critical temperature (Tc) of high temperature superconductor (HTS) Bi-2212 varies with doping content changing. When the Bi-2212 doping content is optimal, the electron energy is near the superconducting constrain gap, also the cohesive energy that the Cooper Pair electrons becoming needed is decreasing, so these electrons can turn into the superconducting cooper pairs more easily under the optimal content. In addition, with the optimal doping content, the densities of the superconductive electronics near Fermi surface increase to the maximum, which causes the number of becoming Cooper Pair electrons is increasing. Base on the two factors discussing above, the electrons can be induced to the superconducting electrons under higher temperature, thus the transition temperature of Bi-2212 increases. Last, this paper also discussed the calculation of the H2S under high pressure, it is known from the calculating results that the bond between the atoms can be destroyed because of the lattice contraction under high pressure. We speculate that the distribution of the electrons does not satisfy the Pauli Exclusion Principle under high pressure, but in a form liking "crowded". When the H2S is loaded voltage under high pressure, the "crowded" electrons can move as the carrier and form the electronic current, in the processing, due to the collision does not occur between electrons, thus the variation of the electron momentum is zero, so the H2S shows the zero resistance phenomenon in the Room temperature under high pressure.
更新日期/Last Update: 2017-04-28