Topological superconducting phase in high-T-c superconductor MgB2 with Dirac-nodal-line fermions

Jin, Kyung-Hwan1; Huang, Huaqing1; Mei, Jia-Wei1,2,3; Liu, Zheng4; Lim, Lih-King4; Liu, Feng1,5

2019-05-03

10.1038/s41524-019-0191-2

npj Computational Materials   影响因子和分区

2057-3960

2057-3960

Topological superconductors are an intriguing and elusive quantum phase, characterized by topologically protected gapless surface/edge states residing in a bulk superconducting gap, which hosts Majorana fermions. Unfortunately, all currently known topological superconductors have a very low transition temperature, limiting experimental measurements of Majorana fermions. Here we discover the existence of a topological Dirac-nodal-line state in a well-known conventional high-temperature superconductor, MgB2. First-principles calculations show that the Dirac-nodal-line structure exhibits a unique one-dimensional dispersive Dirac-nodal line, protected by both spatial-inversion and time-reversal symmetry, which connects the electron and hole Dirac states. Most importantly, we show that the topological superconducting phase can be realized with a conventional s-wave superconducting gap, evidenced by the topological edge mode of the MgB2 thin films showing chiral edge states. Our discovery may enable the experimental measurement of Majorana fermions at high temperature.

SCI ; EI

英语

其他

DOE-BES[DE-FG02-04ER46148]

Chemistry ; Materials Science

Chemistry, Physical ; Materials Science, Multidisciplinary

WOS:000466948300002

SPRINGERNATURE

20201608455900

Magnesium compounds ; Superconducting films ; Shear waves ; Calculations ; Quantum theory ; High temperature superconductors

Superconducting Materials:708.3 ; High Temperature Superconducting Materials:708.3.1 ; Mathematics:921 ; Combinatorial Mathematics, Includes Graph Theory, Set Theory:921.4 ; Mechanics:931.1 ; Quantum Theory; Quantum Mechanics:931.4

Web of Science

1.Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 USA
2.Southern Univ Sci & Technol, Inst Quantum Sci & Engn, Shenzhen 518055, Peoples R China
3.Southern Univ Sci & Technol, Dept Phys, Shenzhen 518055, Peoples R China
4.Tsinghua Univ, Inst Adv Study, Beijing 100084, Peoples R China
5.Collaborat Innovat Ctr Quantum Matter, Beijing 100084, Peoples R China

Jin, Kyung-Hwan,Huang, Huaqing,Mei, Jia-Wei,et al. Topological superconducting phase in high-T-c superconductor MgB2 with Dirac-nodal-line fermions[J]. npj Computational Materials,2019,5.

Jin, Kyung-Hwan,Huang, Huaqing,Mei, Jia-Wei,Liu, Zheng,Lim, Lih-King,&Liu, Feng.(2019).Topological superconducting phase in high-T-c superconductor MgB2 with Dirac-nodal-line fermions.npj Computational Materials,5.

Jin, Kyung-Hwan,et al."Topological superconducting phase in high-T-c superconductor MgB2 with Dirac-nodal-line fermions".npj Computational Materials 5(2019).