Complex Dirac-like Electronic Structure in Atomic Site Ordered Rh3In3.4Ge3.6

Bibliographic Details
Title: Complex Dirac-like Electronic Structure in Atomic Site Ordered Rh3In3.4Ge3.6
Authors: Savvidou, Aikaterini Flessa, Clark, Judith K., Wang, Hua, Wei, Kaya, Choi, Eun Sang, Mozaffari, Shirin, Qian, Xiaofeng, Shatruk, Michael, Balicas, Luis
Source: Chem. Mater. (2021)
Publication Year: 2021
Collection: Condensed Matter
Subject Terms: Condensed Matter - Materials Science, Condensed Matter - Other Condensed Matter
More Details: We report the synthesis via an indium flux method of a novel single-crystalline compound Rh3In3.4Ge3.6 that belongs to the cubic Ir3Ge7 structure type. In Rh3In3.4Ge3.6, the In and Ge atoms choose to preferentially occupy, respectively, the 12d and 16f sites of the Im-3m space group, thus creating a colored version of the Ir3Ge7 structure. Like the other compounds of the Ir3Ge7 family, Rh3In3.4Ge3.6 shows potential as a thermoelectric displaying a relatively large power factor, PF ~ 2 mW/cmK2, at a temperature T ~ 225 K albeit showing a modest figure of merit, ZT = 8 x 10-4, due to the lack of a finite band gap. These figures might improve through a use of chemical substitution strategies to achieve band gap opening. Remarkably, electronic band structure calculations reveal that this compound displays a complex Dirac-like electronic structure relatively close to the Fermi level. The electronic structure is composed of several Dirac type-I and type-II nodes, and even Dirac type-III nodes that result from the touching between a flat band and a linearly dispersing band. This rich Dirac-like electronic dispersion offers the possibility to observe Dirac type-III nodes and study their role in the physical properties of Rh3In3.4Ge3.6 and related Ir3Ge7-type materials.
Comment: 20 pages, including supplementary information file. 10 figures plus 3 supplementary figures
Document Type: Working Paper
DOI: 10.1021/acs.chemmater.0c03943
Access URL: http://arxiv.org/abs/2102.01793
Accession Number: edsarx.2102.01793
Database: arXiv
More Details
DOI:10.1021/acs.chemmater.0c03943