TY - JOUR

T1 - Electronic structure of (Mn1-x⁢Pbx)⁢Bi2⁢Te4: Experimental evidence of topological phase transition

AU - Естюнин, Дмитрий Алексеевич

AU - Макарова, Татьяна Павловна

AU - Klimovskikh, Ilya I.

AU - Бокай, Кирилл Андреевич

AU - Голяшов, Владимир Андреевич

AU - Кох, Константин Александрович

AU - Терещенко, Олег Евгеньевич

AU - Ideta, S.

AU - Miyai, Y.

AU - Kumar, Y.

AU - Iwata, T.

AU - Kosa, T.

AU - Okuda, T

AU - Miyamoto, K

AU - Kuroda, K.

AU - Shimada, K.

AU - Шикин, Александр Михайлович

PY - 2025/5/19

Y1 - 2025/5/19

N2 - This study investigates methods for controlling the physical properties of the intrinsic magnetic topological insulator MnBi$_2$Te$_4$ (MBT) by substituting Mn with Pb in Mn$_{1-x}$Pb$_x$Bi$_2$Te$_4$ (MPBT) solid solutions. This substitution enables tunable magnetic and electronic properties. Using various angle-resolved photoemission spectroscopy (ARPES) techniques, including spin-resolved and circular dichroism (CD) measurements, we analyzed the evolution of the electronic structure across different Pb concentrations, with a focus on topological phase transitions (TPT) near x = 50 %. Key indicators of TPT include the presence or absence of topological surface states (TSS) and bulk band gap closure. The results show a gradual decrease of the bulk band gap in the electronic structure of MPBT up to x = 40 %, where it nearly vanishes, followed by a constant gap value between 40 - 60 %, and its reopening above 80 %, which is accompanied by a transition of the electronic structure of MPBT to a PbBi$_2$Te$_4$-like electronic structure. TSS were observed at x less than 30 % and greater than 80 %, as confirmed by CD and spin-resolved ARPES data, but were absent near x = 55 %, suggesting a distinct topological phase - possibly semi-metallic or a trivial insulator with a narrow gap phase. These findings demonstrate the tunability of the electronic structure of MPBT, making it a promising candidate for topological and spintronic applications.

AB - This study investigates methods for controlling the physical properties of the intrinsic magnetic topological insulator MnBi$_2$Te$_4$ (MBT) by substituting Mn with Pb in Mn$_{1-x}$Pb$_x$Bi$_2$Te$_4$ (MPBT) solid solutions. This substitution enables tunable magnetic and electronic properties. Using various angle-resolved photoemission spectroscopy (ARPES) techniques, including spin-resolved and circular dichroism (CD) measurements, we analyzed the evolution of the electronic structure across different Pb concentrations, with a focus on topological phase transitions (TPT) near x = 50 %. Key indicators of TPT include the presence or absence of topological surface states (TSS) and bulk band gap closure. The results show a gradual decrease of the bulk band gap in the electronic structure of MPBT up to x = 40 %, where it nearly vanishes, followed by a constant gap value between 40 - 60 %, and its reopening above 80 %, which is accompanied by a transition of the electronic structure of MPBT to a PbBi$_2$Te$_4$-like electronic structure. TSS were observed at x less than 30 % and greater than 80 %, as confirmed by CD and spin-resolved ARPES data, but were absent near x = 55 %, suggesting a distinct topological phase - possibly semi-metallic or a trivial insulator with a narrow gap phase. These findings demonstrate the tunability of the electronic structure of MPBT, making it a promising candidate for topological and spintronic applications.

UR - http://arxiv.org/abs/2411.10390

UR - https://www.mendeley.com/catalogue/eba66a8f-8dc0-3eaa-8b55-51b9464863bf/

U2 - 10.1103/PhysRevResearch.7.023168

DO - 10.1103/PhysRevResearch.7.023168

M3 - Article

VL - 7

JO - Physical Review Research

JF - Physical Review Research

SN - 2643-1564

M1 - 023168

ER -