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arXiv · 0905.2971

Charge 2e Boson Underlies Two - Fluid Model of the Pseudogap in Cuprate Superconductors

Shiladitya Chakraborty·Philip Phillips
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Abstract

Starting from the effective low energy theory of a doped Mott insulator, we show that the effective carrier density in the underdoped regime agrees with a two - fluid description. Namely, it has distinct temperature independent and thermally activated components. We identify the thermally activated component as the bound state of a hole and a charge 2e boson, which occurs naturally in the effective theory. The thermally activated unbinding of this state leads to the strange metal and subsequent $T-$linear resistivity. We find that the doping dependence of the binding energy is in excellent agreement with the experimentally determined pseudogap energy scale in cuprate superconductors.

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Shiladitya Chakraborty, Philip Phillips. 2009-05-18. Charge 2e Boson Underlies Two - Fluid Model of the Pseudogap in Cuprate Superconductors. https://doi.org/10.1103/physrevb.80.132505

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