# Reversible doping and fine-tuning of the Dirac point position in the topological crystalline insulator Pb1−xSnxSe via sputtering and annealing process

## TL;DR

This paper shows how sputtering and annealing can clean and fine-tune the electronic properties of a topological material without damaging its structure.

## Contribution

A reversible method for tuning the Dirac point position in Pb1−xSnxSe using sputtering and annealing is introduced.

## Key findings

- Annealing between 250 °C and 280 °C produces smooth surfaces while preserving topological properties.
- Fine control of annealing temperature allows reversible tuning of the Dirac point energy relative to the Fermi level.

## Abstract

In this study, we utilize scanning tunneling microscopy and spectroscopy to detail a sputter- and annealing methodology for preparing atomically clean Pb1−xSnxSe(001) surfaces. We examine the impact these processes have on the surface quality, the composition, and the electronic properties. Our findings demonstrate that annealing temperatures between 250 °C and 280 °C produce smooth surfaces while maintaining the topological properties of Pb1−xSnxSe. Fine control of the annealing temperature also allows for a reversible tuning of the doping level, enabling a positive or negative shift of the Dirac point energy with respect to the Fermi level. Our results highlight the effectiveness of these cleaning methods and demonstrate their potential for future research and applications in topological crystalline insulator materials.

We show that sputter-annealing a multicomponent topological material (Pb1−xSnxSe) enables reversible tuning of the chemical potential while preserving its topological properties and achieving an atomically smooth surface.