Landscape of competing stripe orders in cuprate superconductors: first-principles interplay of spin, charge, and lattice degrees of freedom 

Yubo Zhang (张玉波) 

Department of Physics and Engineering Physics, Tulane University, New Orleans, USA 

时间：2018年7月19日（星期四）13:00 

地点：长宁园区2号楼607会议室 

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联系人：刘建军（52412801） 

　　报告内容:  

　　We have recently demonstrated that the new SCAN metaGGA density functional theory (DFT) correctly describes the ground states of cuprates, thereby opening the way to the parameter-free studies of these complex materials. Here by using SCAN we provide unprecedented first-principles description of stripe states in high-Tc cuprate YBa₂Cu₃O₇ (hole doped phase) and the precursor stripe states in YBa₂Cu₃O₆ (pristine undoped phase). Remarkably, while the precursor stripe states are relatively high in energy, as compared to the antiferromagnetic (AFM) ground state, a large number of stripe states are essentially degenerate with the AFM state in YBa₂Cu₃O₇. These nearly degenerate states are very suggestive of the pseudogap phase which is dominated by fluctuations. Moreover, we find that the non-magnetic state has a much higher energy – that is, the non-magnetic Fermi liquid state in YBa₂Cu₃O₇ is not relevant to the mysterious properties of cuprates. Our simulation also clearly indicates that lattice distortions cannot be disentangled from the stripe states and an accurate description of stripe states should include spin, charge, and lattice degrees of freedom on the same footing. This work on stripes provides a realistic model for studying the cuprate pseudogap phase with implications for pairing electrons in the superconducting phase. 

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　　相关文章列表:  

　　1. Jianwei Sun*, Richard C. Remsing, Yubo Zhang, Zhaoru Sun, Adrienn Ruzsinszky, Haowei Peng, Zenghui Yang, Arpita Paul, Umesh Waghmare, Xifan Wu, Michael L. Klein, and John P. Perdew, Accurate Structures and Energies of Diversely-Bonded Materials from an Efficient Density Functional. Nat. Chem. 8, 831 (2016).  

　　2. Yubo Zhang, Daniil A. Kitchaev, Julia Yang, Tina Chen, Stephen T. Dacek, Haowei Peng*, Gerbrand Ceder, John P. Perdew, and Jianwei Sun*, Efficient first-principles prediction of solid stability: Towards chemical accuracy. npj Comp. Mat. 4, 9 (2018).  

　　3. Yubo Zhang, Jianwei Sun*, John Perdew, and Xifan Wu*, Comparative first-principles studies of prototypical ferroelectric materials by LDA, GGA, and SCAN meta-GGA. Phys. Rev. B 96, 035143 (2017). 

　　4. James W. Furness, Yubo Zhang, Christopher Lane, Ioana Gianina Buda, Bernardo Barbiellini, Robert S. Markiewicz, Arun Bansil*, and Jianwei Sun*, An accurate first-principles treatment of doping dependent electronic structure of high-temperature cuprate superconductors. Nat. Comm. Phys. 1, 11 (2018).  

　　5. Yubo Zhang, Christopher Lane, James W. Furness, Bernardo Barbiellini, Robert S. Markiewicz, Arun Bansil*, and Jianwei Sun*, Quasi-degenerate Ground States in the Pseudogap Phase of Cuprates: interplay between spin, charge, and lattice degrees of freedom. Submitted. 

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