MBa_2Cu_3O_(7-δ)( M=Y,Sm,Gd,Eu)高温超导体的远红外反射光谱  

FAR-INFRARED REFLECTION SPECTRA OF THE HIGH-T_c OXIDE SUPERCONDUCTORS MBa_2Cu_3O_(7-8) (M = Y, Sm, Gd, Eu)

作　　者：叶红娟[1] 俞志毅[1] 陆卫[1] 陈建湘[1] 沈学础[1] 曹宁[2] 郑家琪[2] 陈熙琛[2] 缪柏财[3] 

机构地区：[1]中国科学院上海技术物理研究所 [2]中国科学院物理研究所 [3]复旦大学物理系

出　　处：《物理学报》1989年第5期761-767,共7页Acta Physica Sinica

摘　　要：本文报道多晶MBa_2Cu_3O_(7-8)(M=Y,Sm,Gd,Eu)高温超导体的远红外反射光谱,其频率和温度范围分别为40--360cm^(-1)和 4.2--300K。对于不同M的样品,反射光谱具有相似的结构。在测量范围内,所有样品都有5个反射峰,最低频率的两个峰均属B_(iv)对称类,分别对应Ba,Cu,O离子团振动以及M,O离子团振动,其余3个峰来自CU—O键的弯曲振动;另外,不同M的样品的反射率曲线都具有三处反转结构,即正常态和超导态的反射率曲线的高低位置发生互换。这些反转结构可能与超导能隙有关。The farinfrared reflection spectra of the oxide superconductors MBa2Cu3O(7-δ) (M = Y Sm, Gd, Eu) are reported in this paper. The spectra cover the frequency region of 40-360 cm(-1), and the temperature varies from 4.2 K to 300 K. All the spectra of this series of oxide superconductors exhibit the same kind of structure: there are five reflection peaks and three inversion structures. The first two peaks at lower frequencies are identified to be associated with the collective vibrations of Ba, Cu, O ions and M, O ions, with B1u symmetry; other three peaks result from the bending vibrations of the Cu-O bonds. The three inversion structures in the spectra may be correlated to the superconducting energy gaps.

关 键 词：超导体 高温 红外 反射 光谱 

分 类 号：TM26[一般工业技术—材料科学与工程]