Superconducting materials with high critical temperature have the potential to revolutionize many fields,including military,electronic communications,and power energy.Therefore,scientists around the world have been ti...Superconducting materials with high critical temperature have the potential to revolutionize many fields,including military,electronic communications,and power energy.Therefore,scientists around the world have been tirelessly working with the ultimate goal of achieving high-temperature superconductivity.In 2023,a preprint by Lee et al.in South Korea claimed the discovery of ultra-high-temperature superconductivity with a critical temperature of up to 423 K in Cu-doped lead-apatite(LK-99)(arXiv:2307.12008,arXiv:2307.12037),which caused a worldwide sensation and attention.Herein,the electronic structures,phonon dynamics,and electrical conductivities of LK-99 and its parent compound lead-apatite have been calculated using first-principles methods.The results show that the lead-apatite compound and the LK-99 compound are insulator and half-metal respectively.The flat band characteristic is consistent with previous calculations.The electrical conductivity of the LK-99 compound shows two extreme points,and the electrical conductivity along the C-axis increases significantly after 400 K.The phonon dispersion spectra of the compounds were investigated,demonstrating their dynamic instability.展开更多
基金supported by the National Natural Science Foun-dation of China(Nos.11921006,11975034,11375018,12005048,12335017,U20B2025,and U21B2082)the Beijing Municipal Natural Science Foundation(1222023)the Shenzhen Science and Technology Program(RCYK20210609103904028).
文摘Superconducting materials with high critical temperature have the potential to revolutionize many fields,including military,electronic communications,and power energy.Therefore,scientists around the world have been tirelessly working with the ultimate goal of achieving high-temperature superconductivity.In 2023,a preprint by Lee et al.in South Korea claimed the discovery of ultra-high-temperature superconductivity with a critical temperature of up to 423 K in Cu-doped lead-apatite(LK-99)(arXiv:2307.12008,arXiv:2307.12037),which caused a worldwide sensation and attention.Herein,the electronic structures,phonon dynamics,and electrical conductivities of LK-99 and its parent compound lead-apatite have been calculated using first-principles methods.The results show that the lead-apatite compound and the LK-99 compound are insulator and half-metal respectively.The flat band characteristic is consistent with previous calculations.The electrical conductivity of the LK-99 compound shows two extreme points,and the electrical conductivity along the C-axis increases significantly after 400 K.The phonon dispersion spectra of the compounds were investigated,demonstrating their dynamic instability.