New polymorphic phase and rich phase diagram in the PdSe2-xTex system

Abstract

We report a combined experimental and theoretical study of the PdSe2-xTex system. With increasing Te fraction, structural evolutions, first from an orthorhombic phase (space group Pbca) to a monoclinic phase (space group C2/c) and then to a trigonal phase (space group P-3m1), are observed accompanied with clearly distinct electrical transport behavior. The monoclinic phase (C2/c) is a completely new polymorphic phase and is discovered within a narrow range of Te composition (0.3 \leq x \leq 0.8). This phase has a different packing sequence from all known transition metal dichalcogenides to date. Electronic calculations and detailed transport analysis of the new polymorphic PdSe1.3Te0.7 phase are presented. In the trigonal phase region, superconductivity with enhanced critical temperature is also observed within a narrow range of Te content (1.0 \leq x \leq 1.2). The rich phase diagram, new polymorphic structure as well as abnormally enhanced superconductivity could further stimulate more interest to explore new types of polymorphs and investigate their transport and electronic properties in the transition metal dichalcogenides family that are of significant interest.

arXiv comment16 pages, 7 figures

References in corpus (18)

• 2D materials and van der Waals heterostructures
• Van der Waals Density Functional for General Geometries
• Topological Materials: Weyl Semimetals
• Hopping Transport through Defect-induced Localized States in Molybdenum Disulfide
• Observation of Moiré Excitons in WSe2/WS2 Heterostructure Superlattices
• Magic continuum in twisted bilayer WSe2
• Observation of the Quantum Spin Hall Effect up to 100 Kelvin in a Monolayer Crystal
• Gate-tunable Phase Transitions in 1T-TaS${}_2$
• Electron Transport in Disordered Graphene Nanoribbons
• Observation of the Type-II Weyl Semimetal Phase in MoTe2
• Nontrivial Berry phase and type II Dirac transport in layered material PdTe2
• Quasiparticle Band Gaps, Excitonic Effects, and Anisotropic Optical Properties of Monolayer Distorted 1-T Diamond-chain Structures
• Polytypism, polymorphism and superconductivity in TaSe2-xTex
• Type I superconductivity in the Dirac semimetal PdTe2
• Proximity-Induced Superconductivity with Subgap Anomaly in Type II Weyl Semi-Metal WTe2
• Detailed study on the Fermi surfaces of the type-II Dirac semimetallic candidates PdTe2 and PtTe2
• Direct observation of minibands in twisted heterobilayers
• Enhanced Superconductivity in the Se-substituted 1T-PdTe${}_2$

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• Synthesis of layered gold tellurides AuSbTe and Au${}_2$Te${}_3$ and their semiconducting and metallic behavior