Nodeless high-Tc superconductivity in highly-overdoped monolayer CuO<sub>2</sub>
ORAL
Abstract
We study the electronic structure and superconductivity in CuO2 monolayer grown recently on d-wave cuprate superconductor Bi2Sr2CaCu2O8+δ. Density functional theory calculations indicate significant charge transfer across the interface such that the CuO2 monolayer is heavily overdoped into the hole-rich regime. We show that both the Cu dx2−y2 and d3z2−r2 orbitals become important and the Fermi surface contains one electron and one hole pocket associated with the two orbitals respectively. The liberated low-energy d3z2−r2 band and the hole FS pocket around M enable an analogy to the multiorbital Fe-pnictides superconductors. Constructing a minimal strongly correlated two-orbital model for the eg complex, we show that the spin-orbital exchange interactions produce an intrinsic nodeless superconductor with extended s-wave pairing symmetry and a pairing energy gap comparable to the bulk d-wave gap, in agreement with recent experiments. The findings point to a direction of realizing new high-Tc superconductors over-extended doping regimes with liberated orbitals in ozone grown transition-metal-oxide heterostructures.
*The work is supported by the U.S. Department of Energy, Basic Energy Sciences Grant No. DE-FG02-99ER45747.
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Presenters
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Kun Jiang
- Department of Physics, Boston College
- Boston College
- Physics, Boston College