Optimized flexible Bi2Te3/FeNi spintronic heterostructure for high-efficiency terahertz emission

Y Yuhang Pu (Key Laboratory for Magnetism and Magnetic Functional Materials of Ministry of Education, School of Physical Science and Technology, Lanzhou University 1 , Lanzhou 730000,) C Chenxia Guo (Key Laboratory for Magnetism and Magnetic Functional Materials of Ministry of Education, School of Physical Science and Technology, Lanzhou University , Lanzhou,) Q Qi Zhang X Xi Guo H Haiming Xu T Tong Li Y Yong Xiao D Dezheng Yang (Key Laboratory for Magnetism and Magnetic Functional Materials of Ministry of Education, School of Physical Science and Technology, Lanzhou University , Lanzhou,) Y Yalu Zuo (Key Laboratory for Magnetism and Magnetic Functional Materials of Ministry of Education, School of Physical Science and Technology, Lanzhou University , Lanzhou,) B Baoshan Cui (Key Laboratory for Magnetism and Magnetic Functional Materials of Ministry of Education, School of Physical Science and Technology, Lanzhou University , Lanzhou,) L Li Xi H Huaping Zuo (National Key Laboratory on Vacuum Technology and Physics, Lanzhou Institute of Physics 2 , Lanzhou 730000,) X Xiaoxi Liu

Abstract

Flexible spintronic heterostructure based on topological insulators (TI) enables terahertz (THz) generation for spectroscopy and next-generation communications. Challenges remain in enhancing THz intensity and mechanical durability. Here, Bi2Te3(10 nm)/FeNi(3 nm) on polyimide substrates was optimized via growth temperature tuning and Pt interlayer insertion. The heterostructure shows a 3.8-fold THz enhancement over single layers, attributed to topological surface states (TSSs) of Bi2Te3. Pt interlayer (1.5 nm) boosts emission by 467% (vs no Pt) and 17% (vs Pt/FeNi bilayer) via the inverse spin Hall effect of Pt and preserved TSSs of the TI. Devices retain 98% THz emission after 1200 bending cycles, highlighting potential for flexible THz emission.

Article Details

Volume / Issue Vol. 128, Issue 17
Published April 27, 2026
ISSN 0003-6951
Publisher American Institute of Physics

Journal Info

Applied Physics Letters

American Institute of Physics

ISSN: 0003-6951 Physical Sciences

Authors (13)

Y

Yuhang Pu

Key Laboratory for Magnetism and Magnetic Functional Materials of Ministry of Education, School of Physical Science and Technology, Lanzhou University 1 , Lanzhou 730000,

C

Chenxia Guo

Key Laboratory for Magnetism and Magnetic Functional Materials of Ministry of Education, School of Physical Science and Technology, Lanzhou University , Lanzhou,

Q

Qi Zhang

X

Xi Guo

H

Haiming Xu

T

Tong Li

Y

Yong Xiao

D

Dezheng Yang

Key Laboratory for Magnetism and Magnetic Functional Materials of Ministry of Education, School of Physical Science and Technology, Lanzhou University , Lanzhou,

Y

Yalu Zuo

Key Laboratory for Magnetism and Magnetic Functional Materials of Ministry of Education, School of Physical Science and Technology, Lanzhou University , Lanzhou,

B

Baoshan Cui

Key Laboratory for Magnetism and Magnetic Functional Materials of Ministry of Education, School of Physical Science and Technology, Lanzhou University , Lanzhou,

L

Li Xi

H

Huaping Zuo

National Key Laboratory on Vacuum Technology and Physics, Lanzhou Institute of Physics 2 , Lanzhou 730000,

X

Xiaoxi Liu