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arXiv · 0908.0576

From underdoped to overdoped cuprates: two quantum phase transitions

S. G. Ovchinnikov·E. I. Shneyder·M. M. Korshunov
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Abstract

Several experimental and theoretical studies indicate the existence of a critical point separating the underdoped and overdoped regions of the high-T_c cuprates' phase diagram. There are at least two distinct proposals on the critical concentration and its physical origin. First one is associated with the pseudogap formation for p<p*, with p~0.2. Another one relies on the Hall effect measurements and suggests that the critical point and the quantum phase transition (QPT) take place at optimal doping, p_{opt}~0.16. Here we have performed a precise density of states calculation and found that there are two QPTs and the corresponding critical concentrations associated with the change of the Fermi surface topology upon doping.

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S. G. Ovchinnikov, E. I. Shneyder, M. M. Korshunov. 2011-01-13. From underdoped to overdoped cuprates: two quantum phase transitions. https://doi.org/10.1088/0953-8984%2F23%2F4%2F045701

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