Nonmonotonic dₓ2₋y2 superconducting gap in electron-doped Pr0.89LaCe0.11CuO4: Evidence of coexisting antiferromagnetism and superconductivity?
Originally published in Physical Review B v.74 (2006): 020506(R). DOI: 10.1103/PhysRevB.74.020506
Recent experiments on Pr0.89LaCe0.11CuO₄ observe an anisotropic spin-correlation gap and a nonmonotonic superconducting (SC) gap, which we analyze within the framework of a t-t′-t″-t‴-tiv-U model with a dₓ2−y2 pairing interaction including a third-harmonic contribution. By introducing a realistic broadening of the quasiparticle spectrum to reflect small-angle scattering, our computations explain the experimental observations, especially the presence of a maximum in the leading-edge gap in the vicinity of the hot spots. Our analysis suggests that the material behaves like a two-band superconductor with the d-wave third harmonic acting as the interband pairing gap, and that the antiferromagnetic and SC orders coexist in a uniform phase.
Tanmoy Das, R. S. Markiewicz, and A. Bansil. "Nonmonotonic dₓ2₋y2 superconducting gap in electron-doped Pr0.89LaCe0.11CuO4: Evidence of coexisting antiferromagnetism and superconductivity?" Physics Faculty Publications (2006).
Available at: http://works.bepress.com/abansil/57