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Light Helicity as a Probe for Thickness-Controlled Topological States in α-Sn/CdTe(110) Heterostructures

Tengfei Liu1, Xiyu Hong2, Zhe Li3

  • 1Institute of Micro/Nano Devices and Solar Cells, School of Physics and Information Engineering, Fuzhou University, Fuzhou 350108, China.

ACS Applied Materials & Interfaces
|February 9, 2026
PubMed
Summary

We discovered a thickness-driven topological phase transition in alpha-tin (α-Sn) thin films. Helicity-dependent photocurrent measurements reveal a shift from 2D to 3D topological insulator states between 5 and 10 nm thickness.

Keywords:
helicity-dependent photocurrentstraintopological insulatortopological phase transitiontopological surface statesα-Sn(110)

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