Ground-state phase diagram of the t-t-J model

We report results of large-scale ground-state density matrix renormalization group (DMRG) calculations on t-$t′$-J cylinders with circumferences 6 and 8. We determine a rough phase diagram that appears to approximate the two-dimensional (2D) system. While for many properties, positive and negative$t′$values ($t′/t=±0.2$) appear to correspond to electron- and hole-doped cuprate systems, respectively, the behavior of superconductivity itself shows an inconsistency between the model and the materials. The$t′<0$(hole-doped) region shows antiferromagnetism limited to very low doping, stripes more generally, and the familiar Fermi surface of the hole-doped cuprates. However, we find$t′<0$strongly suppresses superconductivity. The$t′>0$(electron-doped) region shows the expected circular Fermi pocket of holes around the$(π,π)$point and a broad low-doped region of coexisting antiferromagnetism and d-wave pairing with a triplet p component at wavevector$(π,π)$induced by the antiferromagnetism and d-wave pairing. The pairing for the electron low-doped system with$t′>0$is strong and unambiguous in the DMRG simulations. At larger doping another broad region with stripes in addition to weaker d-wave pairing and striped p-wave pairing appears. In a small doping region near$x=0.08$for$t′∼−0.2$, we find an unconventional type of stripe involving unpaired holes located predominantly on chains spaced three lattice spacings apart. The undoped more »

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NSF-PAR ID:
10307360
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
118
Issue:
44
Page Range or eLocation-ID:
Article No. e2109978118
ISSN:
0027-8424
Publisher:
Proceedings of the National Academy of Sciences
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