Superconductor hole doping

Muller KA (2005) Essential Heterogeneities in Hole-Doped Cuprate Superconductors 114 1-11... 

Essential Heterogeneities in Hole-Doped Cuprate Superconductors... 

Fig. 2. Resistivity-vs.-temperature transition curves for some C j based superconductors. (A) Variation of the hole doping from 1.3 to 3.2 holes per C o molecule. Inset the field-effect transistor geometry used in the experiment. (B) Comparison of optimum hole-doped C ). as grown and intercalated with CHCI3 and CHBrj)...

The response for low doping closely follows a two-fluid type behaviour for low hole doping but which deviates from this at higher doping levels. Schneider and Keller [26] analysed Muon spin relaxation rate o- data and noted universal trends in the reduced transition temperature T for a series of extreme type II superconductors which includes the cuprates and the reduced muon spin relation rate [Pg.300]

Electron—hole asymmetry is encountered in cuprate superconductors.3 In the cuprates, superconductivity occurs in the electron-doped regime, although not as prominently as in the hole-doped regime. The electron-... 

Studies on other high-temperature superconductors Positron annihilation measurements across Tc, coupled with the calculations of PDD have been carried out in a variety of hole-doped superconductors that include YBa2Cu40g [48], Bi-Sr-Ca-Cu-0 [49], and Tl-Ba-Ca-Cu-0 [50, 51] systems. We will not labor with the details here, except to state that a variety of temperature dependencies are seen and these can be rationalized when the results are analysed in terms of positron density distribution and the electron-positron overlap function [39]. These calculations show that the positron s sensitivity to the superconducting transition arises primarily from the ability to probe the Cu-O network in the Cu-0 layer. The different temperature dependencies of lifetime, i.e., both the increase and decrease, can be understood in terms of a model of local electron transfer from the planar oxygen atom to the apical oxygen atom, after taking into account the correct positron density distribution within the unit cell of the cuprate superconductor. 

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