Abstract
The hole numbers at Cu and oxygen sites in the CuO2 plane in a wide variety of high-Tc materials have been extracted from the measured nuclear quadrupole frequency, vQ. The hole number in the [formula omitted] orbit, [formula omitted] is found to be more than 0.85 in La2-xSrxCuO4 (x=0.075-0.24), while decreases to 0.74 in Tl2Ba2Ca2Cu3O10. Thus estimated [formula omitted] is supported by the result that the orbital Knight shift along the c-axis, [formula omitted] increases in proportion to [formula omitted] In contrast to the decrease of [formula omitted] the hole number in the O-2pσ orbit, [formula omitted] increases in going from the La- to the Tl-systems. It has been found that Tc is determined by two parameters about holes, i.e., [formula omitted] and [formula omitted] The former tells the microscopic “doping level” of the CuO2 plane, while a smaller [formula omitted] results in a weaker antifer-romagnetic spin fluctuations of low energy. It has been found that not only a proper [formula omitted] but also a sufficiently small [formula omitted] are needed to obtain a high value of Tc.
Original language | English |
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Pages (from-to) | 2524-2532 |
Number of pages | 9 |
Journal | journal of the physical society of japan |
Volume | 64 |
Issue number | 7 |
DOIs | |
Publication status | Published - Jul 1995 |
Externally published | Yes |
Keywords
- NMR
- T
- high-T oxides
- hole distribution
- hole number
- nuclear quadrupole frequency
ASJC Scopus subject areas
- Physics and Astronomy(all)