A cryogenic solid-state reaction at the interface between Ti and the Bi2Se3 topological insulator

Katja Ferfolja,Matjaz Valant,Silvia Nappini,Mattia Fanetti,Mirco Panighel,Igor Píš,Sandra Gardonio

doi:10.1039/d0tc00863j

Abstract

Titanium deposited on the Bi2Se3 surface reacts (even at 130 K) and forms new phases.

Highlights

topological insulator (TI) have attracted a lot of attention from the scientific community during the last decade due to their intriguing properties
A majority of them are in the form of triangular depressions, while others appear as 2 Å high bright spots
The bimodal island formation on TI was reported for Fe,[26,33] that has a strong interaction with the substrate, and Co adatoms.[37]

Summary

Introduction

TIs have attracted a lot of attention from the scientific community during the last decade due to their intriguing properties. A solid-state redox reaction with significant kinetics at room temperature was observed at the interface yielding titanium selenides and metallic Bi. the solid-state chemical interaction was detected even at the cryogenic temperature (130 K). Upon Ti deposition, new components emerge in Se 3d and Bi 5d core levels (Se2 and Bi2, represented as blue components in Fig. 3), indicating a chemical reaction at the interface.

Results

Conclusion