Dual role of Fe dopants in enhancing stability and charge transfer in (Li0.8Fe0.2)OHFeSe superconductors

被引：17

作者：

Chen, Wei ^{[1
,2
,3
,4
]}

Zeng, Changgan ^{[1
,2
]}

Kaxiras, Efthimios ^{[3
,4
]}

Zhang, Zhenyu ^{[1
,2
]}

机构：

[1] Univ Sci & Technol China, Hefei Natl Lab Phys Sci Microscale, Int Ctr Quantum Design Funct Mat ICQD, Hefei 230026, Anhui, Peoples R China

[2] Univ Sci & Technol China, Synerget Innovat Ctr Quantum Informat & Quantum P, Hefei 230026, Anhui, Peoples R China

[3] Harvard Univ, Dept Phys, Cambridge, MA 02138 USA

[4] Harvard Univ, Sch Engn & Appl Sci, Cambridge, MA 02138 USA

来源：

PHYSICAL REVIEW B | 2016年 / 93卷 / 06期

基金：

中国国家自然科学基金;

关键词：

COEXISTENCE; SRTIO3; ORIGIN; FILMS;

D O I：

10.1103/PhysRevB.93.064517

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The recently discovered (Li0.8Fe0.2)OHFeSe superconductor provides a new platform for exploiting the microscopic mechanisms of high-T-c superconductivity in FeSe-derived systems. Using density functional theory calculations, we first show that substitution of Li by Fe not only significantly strengthens the attraction between the (Li0.8Fe0.2)OH spacing layers and the FeSe superconducting layers along the c axis but also minimizes the lattice mismatch between the two in the ab plane, both favorable for stabilizing the overall structure. Next, we explore the electron injection into FeSe from the spacing layers and unambiguously identify the Fe-0.2 components to be the origin of the dramatically enhanced interlayer charge transfer. We further reveal that the system strongly favors collinear antiferromagnetic ordering in the FeSe layers, but the spacing layers can be either antiferromagnetic or ferromagnetic depending on the Fe-0.2 spatial distribution. Based on these insights, we predict (Li0.8Co0.2)OHFeSe to be structurally stable with even larger electron injection and potentially higher T-c.

引用

页数：5

共 28 条

[1] Atomic and electronic structures of single-layer FeSe on SrTiO3(001): The role of oxygen deficiency [J].

Bang, Junhyeok ;

Li, Zhi ;

Sun, Y. Y. ;

Samanta, Amit ;

Zhang, Y. Y. ;

Zhang, Wenhao ;

Wang, Lili ;

Chen, X. ;

Ma, Xucun ;

Xue, Q. -K. ;

Zhang, S. B. .

PHYSICAL REVIEW B, 2013, 87 (22)

[2] Interfacial effects on the spin density wave in FeSe/SrTiO3 thin films [J].

Cao, Hai-Yuan ;

Tan, Shiyong ;

Xiang, Hongjun ;

Feng, D. L. ;

Gong, Xin-Gao .

PHYSICAL REVIEW B, 2014, 89 (01)

[3] Van der Waals density functional for general geometries -: art. no. 246401 [J].

Dion, M ;

Rydberg, H ;

Schröder, E ;

Langreth, DC ;

Lundqvist, BI .

PHYSICAL REVIEW LETTERS, 2004, 92 (24) :246401-1

[4] Scrutinizing the double superconducting gaps and strong coupling pairing in (Li1-xFex)OHFeSe [J].

Du, Zengyi ;

Yang, Xiong ;

Lin, Hai ;

Fang, Delong ;

Du, Guan ;

Xing, Jie ;

Yang, Huan ;

Zhu, Xiyu ;

Wen, Hai-Hu .

NATURE COMMUNICATIONS, 2016, 7

[5] Semiempirical GGA-type density functional constructed with a long-range dispersion correction [J].

Grimme, Stefan .

JOURNAL OF COMPUTATIONAL CHEMISTRY, 2006, 27 (15) :1787-1799

[6] Revealing the Empty-State Electronic Structure of Single-Unit-Cell FeSe/SrTiO3 [J].

Huang, Dennis ;

Song, Can-Li ;

Webb, Tatiana A. ;

Fang, Shiang ;

Chang, Cui-Zu ;

Moodera, Jagadeesh S. ;

Kaxiras, Efthimios ;

Hoffman, Jennifer E. .

PHYSICAL REVIEW LETTERS, 2015, 115 (01)

[7] Van der Waals density functionals applied to solids [J].

Klimes, Jiri ;

Bowler, David R. ;

Michaelides, Angelos .

PHYSICAL REVIEW B, 2011, 83 (19)

[8] Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set [J].

Kresse, G ;

Furthmuller, J .

PHYSICAL REVIEW B, 1996, 54 (16) :11169-11186

[9] Interfacial mode coupling as the origin of the enhancement of Tc in FeSe films on SrTiO3 [J].

Lee, J. J. ;

Schmitt, F. T. ;

Moore, R. G. ;

Johnston, S. ;

Cui, Y. -T. ;

Li, W. ;

Yi, M. ;

Liu, Z. K. ;

Hashimoto, M. ;

Zhang, Y. ;

Lu, D. H. ;

Devereaux, T. P. ;

Lee, D. -H. ;

Shen, Z. -X. .

NATURE, 2014, 515 (7526) :245-U207

[10] Higher-accuracy van der Waals density functional [J].

Lee, Kyuho ;

Murray, Eamonn D. ;

Kong, Lingzhu ;

Lundqvist, Bengt I. ;

Langreth, David C. .

PHYSICAL REVIEW B, 2010, 82 (08)

← 1 2 3 →