# Elemental topological Dirac semimetal: {\alpha}-Sn on InSb(111)

**Authors:** Cai-Zhi Xu, Yang-Hao Chan, Yige Chen, Peng Chen, Xiaoxiong Wang,, Catherine Dejoie, Man-Hong Wong, Joseph Andrew Hlevyack, Hyejin Ryu,, Hae-Young Kee, Nobumichi Tamura, Mei-Yin Chou, Zahid Hussain, Sung-Kwan Mo, and Tai-Chang Chiang

arXiv: 1703.07488 · 2017-04-06

## TL;DR

This paper reports the discovery of a topological Dirac semimetal phase in epitaxial {\

## Contribution

It demonstrates the realization of a 3D topological Dirac semimetal in elemental {\

## Key findings

- Observation of bulk Dirac cones in {\
- Confirmation that epitaxial strain induces the TDS phase

## Abstract

Three-dimensional (3D) topological Dirac semimetals (TDSs) are rare but important as a versatile platform for exploring exotic electronic properties and topological phase transitions. A quintessential feature of TDSs is 3D Dirac fermions associated with bulk electronic states near the Fermi level. Using angle-resolved photoemission spectroscopy (ARPES), we have observed such bulk Dirac cones in epitaxially-grown {\alpha}-Sn films on InSb(111), the first such TDS system realized in an elemental form. First-principles calculations confirm that epitaxial strain is key to the formation of the TDS phase. A phase diagram is established that connects the 3D TDS phase through a singular point of a zero-gap semimetal phase to a topological insulator (TI) phase. The nature of the Dirac cone crosses over from 3D to 2D as the film thickness is reduced.

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Source: https://tomesphere.com/paper/1703.07488