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arXiv · 1412.4214

Isotope Effect of Underdoped Cuprates in the Yang-Rice-Zhang Model

E. Schachinger·J. P. Carbotte
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Abstract

The underdoped region of the cuprate's phase diagram displays many novel electronic phenomena both in the normal and the superconducting state. Many of these anomalous properties have found a natural explanation within the resonating valence bond spin liquid phenomenological model of Yang-Rice-Zhang (YRZ) which includes the rise of a pseudogap. This leads to Fermi surface reconstruction and profoundly changes the electronic structure. Here we extend previous work to consider the shift in critical temperature on $^{16}$O to $^{18}$O substitution, The isotope effect has been found experimentally to be very small at optimal doping yet to rapidly increase to very large values with underdoping. The YRZ model provides a natural explanation of this behavior and supports the idea of a pairing mechanism which is mainly spin fluctuations with a subdominant $(\sim 10\%)$ phonon contribution.

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E. Schachinger, J. P. Carbotte. 2015-03-11. Isotope Effect of Underdoped Cuprates in the Yang-Rice-Zhang Model. https://doi.org/10.1007/s10948-014-2931-3

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