title: Liquid-liquid phase transition in quasi-two-dimensional supercooled silicon.
abstract: Anomalies of the local structural order in quasi-two-dimensional liquid silicon upon cooling are investigated. Results show that the appearance of the left subpeak in pair correlation functions is the signature of the liquid-liquid phase transition (LLPT). The structural origin of the LLPT is the formation of a crystal-like ordered structure with a short-range scale, which in turn forms the local well-organized paracrystalline region. Unlike in the bulk liquid silicon, the stages of the LLPT and liquid-solid phase transition (LSPT) in the quasi-two-dimensional liquid silicon do not overlap. The crystal-like ordered structures formed in the LLPT are precursors which are prepared for the subsequent LSPT. Also observed was a strong interconnection between the local well-organized paracrystalline region and the transition from the typical metal to the semimetal in the two-dimensional silicon. This study will aid in better understanding of the essential phase change in two-dimensional liquid silicon.
authors: National Engineering Research Central for Rare Earth Materials, General Research Institute for Non-Ferrous Metals, GRIREM Advanced Co. Ltd., Beijing 100088, China.
authors: K
authors: K
authors: Zhang
authors: H
authors: H
authors: Li
authors: Y Y
authors: YY
authors: Jiang