【摘要】 本文报道多晶MBa₂Cu₃O_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。更多还原

【Abstract】 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.更多还原