Low-Temperature Eutectic Synthesis of PtTe2 with Weak Antilocalization and Controlled Layer Thinning

TL;DR

This paper presents a novel low-temperature eutectic liquid-phase synthesis method for producing high-quality, thin PtTe2 metallic TMD crystals with record-high conductivity and weak antilocalization, enabling scalable and controllable growth.

Contribution

It introduces the first low-temperature eutectic synthesis of PtTe2, demonstrating scalable growth, high conductivity, and a new approach for controlled thinning of metallic TMDs.

Findings

Record-high room temperature conductivity of 3.3×10^6 S/m.

First experimental observation of weak antilocalization in PtTe2.

Successful layer-by-layer thinning retaining high crystallinity.

Abstract

Metallic transition metal dichalcogenides (TMDs) have exhibited various exotic physical properties and hold the promise of novel optoelectronic and topological devices applications. However, the synthesis of metallic TMDs is based on gas-phase methods and requires high temperature condition. As an alternative to the gas-phase synthetic approach, lower temperature eutectic liquid-phase synthesis presents a very promising approach with the potential for larger-scale and controllable growth of high-quality thin metallic TMDs single crystals. Herein, we report the first realization of low-temperature eutectic liquid-phase synthesis of type-II Dirac semimetal PtTe2 single crystals with thickness ranging from 2 to 200 nm. The electrical measurement of synthesized PtTe2 reveals a record-high conductivity of as high as 3.3*106 S/m at room temperature. Besides, we experimentally identify the weak antilocalization behavior in the type-II Dirac semimetal PtTe2 for the first time. Furthermore, we develop a simple and general strategy to obtain atomically-thin PtTe2 crystal by thinning as-synthesized bulk samples, which can still retain highly crystalline and exhibits excellent electric conductivity. Our results of controllable and scalable low-temperature eutectic liquid-phase synthesis and layer-by-layer thinning of high-quality thin PtTe2 single crystals offer a simple and general approach for obtaining different thickness metallic TMDs with high-melting point transition metal.