高压物理学报2024，Vol.38Issue(2)：58-69,12.DOI:10.11858/gywlxb.20230791
高压下Y-Si-H体系晶体结构和超导性质的第一性原理研究
Ab Initio Calculation Principles Study of Crystal Structure and Superconducting Properties of Y-Si-H System under High Pressure
摘要
Abstract
Using first principles density functional theory calculations,the crystal structure,electronic properties,and superconductivity characteristics of the ternary hydride Y-Si-H system under high pressure were investigated.The study revealed the existence of thermodynamically stable phases,including YSiH7,YSiH9,YSi2H12,and YSiH18,and thermodynamically metastable phases,namely YSi2H13,YSi2H14,and Y2SiH17.Electronic properties calculations showed that YSiH7 is insulator and YSi2H13 is semiconductor,while the remaining hydrides exhibit metallic properties.Superconducting transition temperatures(Tc)were estimated using the McMillan equation,with YSi2H12 hosting the highest Tc of 43.5 K at 100 GPa.The dynamic stable pressure of YSi2H14 can be reduced to 40 GPa,and its Tc is 23.8 K which is twice the highest Tc among binary Y-Si compounds,indicating that introducing H atom into Y-Si system can effectively increase the superconducting transition temperature.Y2SiH17 exhibits a Tc of 35.8 K at 100 GPa.Spectral function and electron-phonon coupling calculations suggested that in YSi2H14 and Y2SiH17,in addition to the H-induced superconductivity from mid-frequency vibrations,low-frequency vibrations of Y also play a significant role for superconductivity.关键词
高压/氢化物/第一性原理/结构预测/超导电性Key words
high pressure/hydride/first principles/structure prediction/superconductivity分类
数理科学引用本文复制引用
马浩,陈玲,蒋其雯,安德成,段德芳..高压下Y-Si-H体系晶体结构和超导性质的第一性原理研究[J].高压物理学报,2024,38(2):58-69,12.基金项目
国家重点研发计划(2022YFA1402304) （2022YFA1402304）
国家自然科学基金(12122405,122741695) （12122405,122741695）
中央高校基本科研业务费专项资金 （）
