排序方式: 共有29条查询结果,搜索用时 0 毫秒
1.
Temperature dependence of the threshold of pure and impurity-doped blue bronzes has been studied. It is found that for pare blue bronzes the threshold field near 100K has an anomalous peak, but for impurity-doped samples no anomaly is observed in the range of liquid nitrogen temperature, and the value of the threshold field gradu-ally increases with the decrease of temperature. The results show that in the high-quality pure blue bronzes, there may exist an incommensurate to quasi-commensurate transition near 100K. But for the impurity-doped or "dirty" pure samples, such an incommensurate to quasi-commensurate transition near 100K can be extensively re-strained by impurities or defects, which leads to a pure incommensurate CDW in a wide temperature range. 相似文献
2.
3.
Contactless Microwave Detection of Shubnikov–De Haas Oscillations in Three-Dimensional Dirac Semimetal ZrTe_5 下载免费PDF全文
We report Shubnikov–de Haas(SdH)oscillations of a three-dimensional(3D) Dirac semimetal candidate of layered material ZrTe_5 single crystals through contactless electron spin resonance(ESR)measurements with the magnetic field up to 1.4 T.The ESR signals manifest remarkably anisotropic characteristics with respect to the direction of the magnetic field,indicating an anisotropic Fermi surface in ZrTe_5.Further experiments demonstrate that the ZrTe_5 single crystals have the signature of massless Dirac fermions with nontrivialBerry phase,key evidence for 3D Dirac/Weyl fermions.Moreover,the onset of quantum oscillation of our ZrTe_5 crystals revealed by the ESR can be derived down to 0.2 T,much smaller than the onset of SdH oscillation determined by conventional magnetoresistance measurements.Therefore,ESR measurement is a powerful tool to study the topologically nontrivial electronic structure in Dirac/Weyl semimetals and other topological materials with low bulk carrier density. 相似文献
4.
采用碳酸盐替代高钼酸盐电解还原的方法成功制备出了准二维电荷密度波导体钾紫青铜单晶.通过x射线衍射、透射电子显微术等方法对单晶进行结构分析表明:晶胞参数a=b=0.5540nm,c=1.3508nm,单晶为三角晶系,对称群为P3.电阻温度关系曲线的测量显示:钾紫青铜KxMo6O17单晶在112K附近发生金属到金属的Peierls相变.
关键词:
钾紫青铜
电荷密度波
Peierls相变 相似文献
5.
6.
在90~290K范围内对蓝青铜单晶Rb0.3MoO3和Rb0.15MO03的热电势与温度的关系进行了比较研究,发现:1)在180K附近,两种蓝青铜导体的热电势出现突变是这两种物质存在Peierls相变的的又一例证并分别分析了A位元素的完全替代和部分替代对Peierls相变的影响;2)在相变点tp以上和以下,两者的热电有相似的变化,由高温区较小的正值变为低温区较大的负值,并可以用经验关系式S=AT+B/T来描述. 相似文献
7.
在 90~ 2 90 K范围内对蓝青铜单晶 Rb0 .3 Mo O3和 Rb0 .1 5 K0 .1 5 Mo O3的热电势与温度的关系进行了比较研究 ,发现 :1)在 180 K附近 ,两种蓝青铜导体的热电势出现突变是这两种物质存在 Peierls相变的的又一例证并分别分析了 A位元素的完全替代和部分替代对 Peierls相变的影响 ;2 )在相变点 TP以上和以下 ,两者的热电势有相似的变化 ,由高温区较小的正值变为低温区较大的负值 ,并可以用经验关系式 S=AT B/ T来描述 相似文献
8.
测量了 2H Nb0 .9Ta0 .1 Se2 单晶样品在不同电流下电压随磁场变化的曲线V(H) ,并从V(H)曲线得到V(I)数据 .使用标度关系V =α(I-Ic)β进行了拟合 ,得到了临界电流随磁场Ic(H)和微分电阻随磁场Rd 的变化关系 .在微分电阻随磁场变化的曲线中 ,电流较大时 ,靠近上临界磁场Hc2 附近出现一个强峰 ,而在低电流下 ,该峰消失 .同时在临界电流峰效应区的起始处出现一小峰 .实验结果表明掺Ta后 ,涡旋体系的动力学特性发生了显著的变化 . 相似文献
9.
在90~290K范围内对蓝青铜单晶Rb 相似文献
10.
准—维导体铊青铜的熔盐电解制备 总被引:3,自引:1,他引:2
本文详细介绍了一种用熔盐电解方法制备具有电荷密度波(CDW)传输特性的铊青铜的简便方法,生长单晶速度快,质量也较好,一般大小为4×2×1mm^3.电子探针分析表明:晶体成份为 Tl_(0.31)MoO_(3.3),与国外报道的 Tl_(0.3)M_oO_3基本一致. 相似文献