Gapless spin excitations in superconducting La$_{2-x}$Ca$_{1+x}$Cu$_{2}$O$_{6}$ with $T_c$ up to 55 K

John A. Schneeloch; Ruidan Zhong; M. B. Stone; I. A. Zaliznyak; G. D. Gu; Guangyong Xu; J. M. Tranquada

doi:10.1103/PhysRevB.99.174515

paper

Gapless spin excitations in superconducting La $_{2 - x}$ Ca $_{1 + x}$ Cu $_{2}$ O $_{6}$ with $T_{c}$ up to 55 K

arXiv:1902.07799 · doi:10.1103/PhysRevB.99.174515

Abstract

We report inelastic neutron scattering on single crystals of the bilayer cuprate family La $_{2 - x}$ Ca $_{1 + x}$ Cu $_{2}$ O $_{6 + δ}$ , including two crystals made superconducting (transitions at 45 and 55 K) by high-pressure annealing in an oxygen-containing atmosphere. The magnetic excitations in the non-superconducting crystal have a similar temperature-dependence as those in weakly hole-doped cuprates. In the superconducting crystals, there is a near-uniform suppression of the magnetic spectral weight with increasing temperature; in particular, there are no signs of a spin gap or "resonance" peak. This is different from the temperature dependence seen in many optimally-doped cuprates but similar to the behavior seen in certain underdoped cuprates. We discuss the possible connection with pair-density-wave superconductivity.

11 pp, 8 figs, revised version, accepted in PRB

Gapless spin excitations in superconducting La2−x​Ca1+x​Cu2​O6​ with Tc​ up to 55 K

Abstract

References in corpus (18)

Gapless spin excitations in superconducting La $_{2 - x}$ Ca $_{1 + x}$ Cu $_{2}$ O $_{6}$ with $T_{c}$ up to 55 K