Competition between superconductivity and charge stripe order in high-T_c cuprates

Abstract

Members of the high-Tc cuprate family (with defect-free CuO₂ planes) are suggested to have an "Intrinsic single-layer superconducting T_c", larger than the experimentally observed T_c, at a given hole concentration. This difference occurs to varying degrees among the different members due to an anomalous response of the d-wave superconducting state to self-generated charge perturbations. In particular, any quasielastic charge stripe order, arising from electron-electron and electron-lattice coupling, can suppress the large intrinsic superconducting T_c. Existing experimental results on the wide T_c variation in the single-layer cuprate families, such as the low T_c (≈ 38 K, 33 K) of LSCO and Bi-2201 compared to the high-T_c (≈ 95 K, 98 K) of Tl-2201 and Hg-1201, the strain-induced increase in T_c (25 to 50 K) observed in LSCO are qualitatively explained by our mechanism. We predict that under proper epitaxial strain, the T_c of LSCO and Bi-2201 should increase from the 30's all the way up to the intrinsic T_c ~ 90 K at optimal doping.