Angle-resolved photoemission spectroscopy study of the electronic structure evolution in Sn4X3 (X = P, As, Sb)

Autor: Rui-Hua He, Yunhao Lu, Zhi Ren, Zhen Song, Chenqiang Hua, Caiyun Hong, Bin Liu, Geng Zhao, Wei Wen
Rok vydání: 2021
Předmět:
Zdroj: Applied Surface Science. 569:150980
ISSN: 0169-4332
DOI: 10.1016/j.apsusc.2021.150980
Popis: The binary compounds Sn4X3 (X = P, As, Sb) have recently surfaced as a unique platform in which to study the interplay between nontrivial band topology and superconductivity with both strengthening as X varies from P to Sb. Here we perform the first systematic comparison of the electronic structure between the three member compounds. Results of our angle-resolved photoemission spectroscopy experiments on both Sn4Sb3 and Sn4P3 are compared with first-principles bulk and surface electronic structure calculations as well as with those recently reported for Sn4As3. Based on a thorough characterization of the electronic structure in three-dimensional momentum space, three salient aspects have been identified, including a monotonic chemical potential shift in a non-rigid-band fashion, a monotonic variation in the magnitude of a band splitting of surface origin, and the emergence of additional surface-related bands. We show that these observations can be reasonably captured by the evolution of the initial-state band structure given by first-principles calculations, and argue that the covalent bonding between the surface Sn monolayer and the underlying X monolayer, rather than the spin–orbit coupling, likely plays an important role in accounting for the observed differences in the electronic structure across the Sn4X3 family. Our finding depicts a comprehensive picture for the electronic structure evolution in the Sn4X3 family, and paves the way to deciphering the relationship between the nontrivial band topology and superconductivity therein.
Databáze: OpenAIRE
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