张玉波博士来课题组交流访问

SEMINAR 

The State Key Lab of 

High Performance Ceramics and Superfine Microstructure 

Shanghai Institute of Ceramics, Chinese Academy of Sciences 

   

 
 

 

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:2018719日(星期四)13:00 

地点:长宁园区2号楼607会议室 

        

欢迎广大科研人员和研究生参与讨论! 

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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  主讲人简介:  

张玉波:理学博士,目前就职于美国杜兰大学(Tulane University)物理系,研究助理教授。2007-2012年为哈尔滨工业大学与中科院上海硅酸盐研究所的联合培养博士生,2012年获得理学博士学位。2012-2014年,于中科院上海硅酸盐研究所开展博士后研究工作;2014年至今在美国天普大学、德州大学、杜兰大学继续开展博士后及研究助理教授工作。主要研究工作是采用第一原理的理论计算方法,探索光电材料、铁电材料和高温超导材料的基础物性,预测新材料体系并优化其性能。已发表论文24篇,国际学术会议邀请报告3次。