Tuning competition between charge order and superconductivity in the square-lattice t−t′−J model

作     者：Xin Lu Huaiming Guo Wei-Qiang Chen D. N. Sheng Shou-Shu Gong 

作者机构：School of Physics Beihang University Beijing 100191 China Department of Physics and Guangdong Basic Research Center of Excellence for Quantum Science Southern University of Science and Technology Shenzhen 518055 China Shenzhen Key Laboratory of Advanced Quantum Functional Materials and Devices Southern University of Science and Technology Shenzhen 518055 China Department of Physics and Astronomy California State University Northridge Northridge California 91330 USA School of Physical Sciences Great Bay University Dongguan 523000 China Great Bay Institute for Advanced Study Dongguan 523000 China 

出 版 物：《Physical Review B》 (Phys. Rev. B)

年 卷 期：2025年第111卷第3期

页      面：035139-035139页

核心收录：

基　　金：SongShan Lake HPC Center Key Areas for Universities in Guangdong Province, (2023ZDZX3054) National Science Foundation, NSF, (PHY-2216774) National Science Foundation, NSF Dongguan Key Laboratory of Artificial Intelligence Design for Advanced Materials, (2024KCXTD048) National Natural Science Foundation of China, NSFC, (12274014) National Natural Science Foundation of China, NSFC Southern University of Science and Technology, SUSTech, (12074022) Southern University of Science and Technology, SUSTech BNLCMP open research fund, (2024BNLCMPKF023) Guangdong Provincial Quantum Science Strategic Initiative, (SZZX2401001, GDZX2201001) National Key Research and Development Program of China, NKRDPC, (12141402, 2024YFA1408101) National Key Research and Development Program of China, NKRDPC Science, Technology and Innovation Commission of Shenzhen Municipality, (ZDSYS20190902092905285) Science, Technology and Innovation Commission of Shenzhen Municipality 

主　　题：Charge density waves 

摘      要：Recently, a flurry of works have found strong competition between charge density wave (CDW) and superconductivity (SC) in the doped Hubbard and t−J models on the square lattice. Interestingly, some recent results suggest that the electron-phonon coupling may suppress CDW order and enhance SC. In this work, we consider the square-lattice Hubbard model with the Holstein or Su-Schrieffer-Heeger electron-phonon coupling at the large-U and antiadiabatic (infinite phonon frequency) limits, which gives an effective t−J model with either a density attractive interaction V or a JP term that contributes a larger spin exchange and a density repulsive interaction. To explore how these effective couplings may tune the competition between CDW and SC, we implement the density matrix renormalization group simulations on the t−t′−J model with V or JP coupling. We focus on the six-leg cylinder system with the next-nearest-neighbor hopping t′, which hosts partially filled stripe and d-wave SC in phase diagram. By tuning t′/t0 and V or JP, we establish two quantum phase diagrams at 112 doping ratio. In the SC phases, the increased V or JP coupling can enhance the quasi-long-range SC order, consistent with some previous findings. Nonetheless, no SC emerges when the partially filled stripe phase disappears with increased V or JP. Instead, the system has a transition to either a phase-separation-like regime or a filled stripe phase. On the other hand, with increased t′/t, not only the partially filled stripe but the phase separation and filled stripe can also be tuned to SC phase. Our results suggest that although V and JP couplings may strengthen hole binding, the hole dynamics controlled by t′/t appears to play a more crucial role for obtaining a SC in the t−J model.