Pb_{5}Bi_{24}Se_{41}: A New Member of the Homologous Series Forming Topological Insulator Heterostructures

TL;DR

This paper reports the synthesis of a new topological insulator compound, Pb_{5}Bi_{24}Se_{41}, expanding the homologous series known for layered topological heterostructures and revealing insights into their anisotropic transport properties.

Contribution

The study introduces Pb_{5}Bi_{24}Se_{41} as a novel member of the homologous series, demonstrating its potential for tunable topological states and layered heterostructure properties.

Findings

Pb_{5}Bi_{24}Se_{41} synthesized successfully.

Expands the homologous series of layered topological insulators.

Resistivity anisotropy indicates hybridization effects.

Abstract

We have synthesized Pb_{5}Bi_{24}Se_{41}, which is a new member of the (PbSe)_{5}(Bi2Se3)_{3m} homologous series with m = 4. This series of compounds consist of alternating layers of the topological insulator Bi2Se3 and the ordinary insulator PbSe. Such a naturally-formed heterostructure has recently been elucidated to give rise to peculiar quasi-two-dimensional topological states throughout the bulk, and the discovery of Pb_{5}Bi_{24}Se_{41} expands the tunability of the topological states in this interesting homologous series. The trend in the resistivity anisotropy in this homologous series suggests an important role of hybridization of the topological states in the out-of-plane transport.