Flourishing rare earth superhydrides are a class of recently discovered materials that exhibit near-room-temperature superconductivity at high pressures,ushering in a new era of superconductivity research at high pres...Flourishing rare earth superhydrides are a class of recently discovered materials that exhibit near-room-temperature superconductivity at high pressures,ushering in a new era of superconductivity research at high pressures.Yttrium superhydrides drew the most attention among these superhydrides due to their abundance of stoichiometries and excellent superconductivities.Here,we carried out a comprehensive study of yttrium superhydrides in a wide pressure range of 140 GPa-300 GPa.We successfully synthesized a series of superhydrides with the compositions of YH_(4),YH_(6),YH_(7),and YH_(9),and reported superconducting transition temperatures of 82 K at 167 GPa,218 K at 165 GPa,29 K at 162 GPa,and230 K at 300 GPa,respectively,as evidenced by sharp drops in resistance.The structure and superconductivity of YH_(4) were taken as a representative example and were also examined using x-ray diffraction measurements and the superconductivity suppression under external magnetic fields,respectively.Clathrate YH_(10),a candidate for room-temperature superconductor,was not synthesized within the study pressure and temperature ranges of up to 300 GPa and 2000 K.The current study established a detailed foundation for future research into room-temperature superconductors in polynary yttrium-based superhydrides.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2021YFA1400203 and 2018YFA0305900)the National Natural Science Foundation of China(Grant Nos.52090024,11874175,12074139,12074138,11874176,and 12034009)+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB33000000)Program for JLU Science and Technology Innovative Research Team(JLUSTIRT)。
文摘Flourishing rare earth superhydrides are a class of recently discovered materials that exhibit near-room-temperature superconductivity at high pressures,ushering in a new era of superconductivity research at high pressures.Yttrium superhydrides drew the most attention among these superhydrides due to their abundance of stoichiometries and excellent superconductivities.Here,we carried out a comprehensive study of yttrium superhydrides in a wide pressure range of 140 GPa-300 GPa.We successfully synthesized a series of superhydrides with the compositions of YH_(4),YH_(6),YH_(7),and YH_(9),and reported superconducting transition temperatures of 82 K at 167 GPa,218 K at 165 GPa,29 K at 162 GPa,and230 K at 300 GPa,respectively,as evidenced by sharp drops in resistance.The structure and superconductivity of YH_(4) were taken as a representative example and were also examined using x-ray diffraction measurements and the superconductivity suppression under external magnetic fields,respectively.Clathrate YH_(10),a candidate for room-temperature superconductor,was not synthesized within the study pressure and temperature ranges of up to 300 GPa and 2000 K.The current study established a detailed foundation for future research into room-temperature superconductors in polynary yttrium-based superhydrides.
