Surface electronic structure engineering of manganese bismuth tellurides guided by micro-focused angle-resolved photoemission

TY - JOUR

T1 - Surface electronic structure engineering of manganese bismuth tellurides guided by micro-focused angle-resolved photoemission

AU - Volckaert, Klara

AU - Majchrzak, Paulina Ewa

AU - Biswas, Deepnarayan

AU - Jones, Alfred

AU - Bianchi, Marco

AU - Jiang, Zhihao

AU - Dubourg, Raphaël

AU - Stenshøj, Rasmus Ørnekoll

AU - Jensen, Mads Lykke

AU - Jones, Nykola C.

AU - Hoffmann, Søren Vrønning

AU - Mi, Jianli

AU - Bremholm, Martin

AU - Pan, Xing Chen

AU - Chen, Yong P.

AU - Hofmann, Philip

AU - Miwa, Jill

AU - Ulstrup, Søren

PY - 2023/9/7

Y1 - 2023/9/7

N2 - Modification of the electronic structure of quantum matter by ad atom deposition allows for directed fundamental design of electronic and magnetic properties. This concept is utilized in the present study in order to tune the surface electronic structure of magnetic topological insulators based on MnBi 2 Te 4 . The topological bands of these systems are typically strongly electron-doped and hybridized with a manifold of surface states that place the salient topological states out of reach of electron transport and practical applications. In this study, micro-focused angle-resolved photoemission spectroscopy (microARPES) provides direct access to the termination-dependent dispersion of MnBi 2 Te 4 and MnBi 4 Te 7 during in situ deposition of rubidium atoms. The resulting band structure changes are found to be highly complex, encompassing coverage-dependent ambipolar doping effects, removal of surface state hybridization, and the collapse of a surface state band gap. In addition, doping-dependent band bending is found to give rise to tunable quantum well states. This wide range of observed electronic structure modifications can provide new ways to exploit the topological states and the rich surface electronic structures of manganese bismuth tellurides.

AB - Modification of the electronic structure of quantum matter by ad atom deposition allows for directed fundamental design of electronic and magnetic properties. This concept is utilized in the present study in order to tune the surface electronic structure of magnetic topological insulators based on MnBi 2 Te 4 . The topological bands of these systems are typically strongly electron-doped and hybridized with a manifold of surface states that place the salient topological states out of reach of electron transport and practical applications. In this study, micro-focused angle-resolved photoemission spectroscopy (microARPES) provides direct access to the termination-dependent dispersion of MnBi 2 Te 4 and MnBi 4 Te 7 during in situ deposition of rubidium atoms. The resulting band structure changes are found to be highly complex, encompassing coverage-dependent ambipolar doping effects, removal of surface state hybridization, and the collapse of a surface state band gap. In addition, doping-dependent band bending is found to give rise to tunable quantum well states. This wide range of observed electronic structure modifications can provide new ways to exploit the topological states and the rich surface electronic structures of manganese bismuth tellurides.

KW - alkali doping

KW - magnetic topological insulators

KW - microARPES

KW - surface band structure engineering

KW - tunable topological bands

U2 - 10.1002/adma.202301907

DO - 10.1002/adma.202301907

M3 - Journal article

C2 - 37204117

SN - 0935-9648

VL - 35

JO - Advanced Materials

JF - Advanced Materials

IS - 36

M1 - 2301907

ER -