Optical Study of the Sr-14-xCaxCu O-2441 System: Evidence for Hole-Doped Cu O-23 Ladders
Optical Study of the Sr-14-xCaxCu O-2441 System: Evidence for Hole-Doped Cu O-23 Ladders
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Sr-14-xCaxCu O-2441 系统的光学研究：空穴掺杂 Cu O-23 梯子的证据
DOI：
10.1103/physrevlett.78.1980
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发表时间：
1997
影响因子：
8.6
通讯作者：
S. Uchida
中科院分区：
文献类型：
--
作者：
T. Osafune;N. Motoyama;H. Eisaki;S. Uchida
研究了由两条Cu2O3阶梯和共享边的CuO2链组成的Sr14−xCaxCu24O41晶体在不同组分下的电导谱。当等价的Ca取代Sr的光谱重量的快速转移发生从高能量到低能量区域，基本上以相同的方式观察到的高Tc的铜酸盐的掺杂的CuO 2平面。我们确定这种行为的后果链和梯子之间的电荷重新分配，并估计在每个结构单元的空穴密度从转移的光谱重量。
The optical conductivity spectrum of Sr14−xCaxCu24O41, composed of two-leg Cu2O3 ladders and edge-sharing CuO2 chains, is investigated on single crystals with various compositions. Upon isovalent Ca substitution for Sr a rapid transfer of the spectral weight takes place from the high- to low-energy region, essentially in the same manner as that observed in the doped CuO2 planes of high- Tc cuprates. We identify this behavior as a consequence of charge redistribution between chains and ladders, and estimate the hole density in each structural unit from the transferred spectral weight.