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arXiv · 0705.0299

Charge transfer mechanism and Tc(x) dependence in Y0.8(Ca)0.2Ba2Cu3O6+x

V. M. Matic·N. Dj. Lazarov·I. M. Bradaric
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Abstract

We propose a model for charge transfer mechanism in Y0.8(Ca)0.2Ba2Cu3O6+x to count hole doping of CuO2 planes and x dependence of critical transition temperature T_c. It is assumed the total number of doped holes in the planes is sum of holes that are introduced through two separate channels: substitution of Y3+ by Ca2+ and from CuO chains that are longer than a minimal (critical) length l_min needed for charge transfer to take place. The T_c(x) dependence is obtained by combining calculated x dependence of doping, p(x), and universal T_c versus p relation. Although calculated T_c(x) dependences for l_min=3 and l_min=4 both remarkably correlate to the experimental T_c(x), we argue that the value l_min=4 gives a reasonable overall agreement.

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V. M. Matic, N. Dj. Lazarov, I. M. Bradaric. 2008-04-09. Charge transfer mechanism and Tc(x) dependence in Y0.8(Ca)0.2Ba2Cu3O6+x. https://doi.org/10.1088/0953-2048%2F21%2F7%2F075012

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