Pressure-induced structural transitions and metallization in ZrSe₂

【摘要】 High-pressure studies of two-dimensional materials have revealed numerous novel properties and physical mechanisms behind them.As a typical material of transition metal dichalcogenides（TMDs）,ZrSe₂ exhibits high carrier mobility,rich electronic states regulated by doping,and high potential in applications at ambient pressure.However,the properties of ZrSe₂ under pressure are still not clear,especially for the structural and electrical properties.Here,we report the investigation of ZrSe₂ under pressure up to 66.5 GPa by in-situ x-ray diffraction,Raman,electrical transport measurements,and first-principles calculations.Two structural phase transitions occur in ZrSe₂ at 8.3 GPa and 31.5 GPa,from P-3m1 symmetry to P2₁/m symmetry,and finally transformed into a non-layer I4/mmm symmetry structure.Pressure-induced metallic transition is observed at around 19.4 GPa in phase Ⅱ which aligns well with the results of the calculation.Our work will help to improve the understanding of the evolution of the structure and electrical transport properties of two-dimensional materials.更多还原

【Abstract】 High-pressure studies of two-dimensional materials have revealed numerous novel properties and physical mechanisms behind them.As a typical material of transition metal dichalcogenides（TMDs）,ZrSe₂ exhibits high carrier mobility,rich electronic states regulated by doping,and high potential in applications at ambient pressure.However,the properties of ZrSe₂ under pressure are still not clear,especially for the structural and electrical properties.Here,we report the investigation of ZrSe₂ under pressure up to 66.5 GPa by in-situ x-ray diffraction,Raman,electrical transport measurements,and first-principles calculations.Two structural phase transitions occur in ZrSe₂ at 8.3 GPa and 31.5 GPa,from P-3m1 symmetry to P2₁/m symmetry,and finally transformed into a non-layer I4/mmm symmetry structure.Pressure-induced metallic transition is observed at around 19.4 GPa in phase Ⅱ which aligns well with the results of the calculation.Our work will help to improve the understanding of the evolution of the structure and electrical transport properties of two-dimensional materials.更多还原