A dream long held by physicists has been to raise the critical temperature(Tc)—the temperature below which the material exhibits no electrical resistance—of a superconductor to room temperature.The most recent excit...A dream long held by physicists has been to raise the critical temperature(Tc)—the temperature below which the material exhibits no electrical resistance—of a superconductor to room temperature.The most recent excitement in that regard has centered on rare-earth superhydrides,of which LaH10 at 190 GPa has a remarkably high Tc of 260 K.展开更多
Semiconductivity and superconductivity are remarkable quantum phenomena that have immense impact on science and technology,and materials that can be tuned,usually by pressure or doping,to host both types of quantum st...Semiconductivity and superconductivity are remarkable quantum phenomena that have immense impact on science and technology,and materials that can be tuned,usually by pressure or doping,to host both types of quantum states are of great fundamental and practical significance.Here we show by first-principles calculations a distinct route for tuning semiconductors into superconductors by diverse large-range elastic shear strains,as demonstrated in exemplary cases of silicon and silicon carbide.Analysis of strain driven evolution of bonding structure,electronic states,lattice vibration,and electron-phonon coupling unveils robust pervading deformation induced mechanisms auspicious for modulating semiconducting and superconducting states under versatile material conditions.This finding opens vast untapped structural configurations for rational exploration of tunable emergence and transition of these intricate quantum phenomena in a broad range of materials.展开更多
Gallium arsenide(GaAs),a typical covalent semiconductor,is widely used in the electronic industry,owing to its superior electron transport properties.However,its brittle nature is a drawback that has so far significan...Gallium arsenide(GaAs),a typical covalent semiconductor,is widely used in the electronic industry,owing to its superior electron transport properties.However,its brittle nature is a drawback that has so far significantly limited its application.An exploration of the structural deformation modes of GaAs under large strain at the atomic level,and the formulation of strategies to enhance its mechanical properties is highly desirable.The stressstrain relations and deformation modes of single-crystal and nanotwinned GaAs under various loading conditions are systematically investigated,using first-principles calculations.Our results show that the ideal strengths of nanotwinned GaAs are 14% and 15% higher than that of single-crystal GaAs under pure and indentation shear strains,respectively,without producing a significantly negative effect in terms of its electronic performance.The enhancement in strength stems from the rearrangement of directional covalent bonds at the twin boundary.Our results offer a fundamental understanding of the mechanical properties of single crystal GaAs,and provide insights into the strengthening mechanism of nanotwinned GaAs,which could prove highly beneficial in terms of developing reliable electronic devices.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.11534003,11874175,11874176,12074138,and 11974134)the Science Challenge Project(Grant No.TZ2016001)+3 种基金the Fundamental Research Funds for the Central Universities(Jilin University,JLU)the Program for JLU Science and Technology Innovative Research Team(JLUSTIRT)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB33000000)the Jilin Province Outstanding Young Talents Project(Grant No.20190103040JH).
文摘A dream long held by physicists has been to raise the critical temperature(Tc)—the temperature below which the material exhibits no electrical resistance—of a superconductor to room temperature.The most recent excitement in that regard has centered on rare-earth superhydrides,of which LaH10 at 190 GPa has a remarkably high Tc of 260 K.
基金the National Key Research and Development Program of China(Grant No.2018YFA0703400)the National Natural Science Foundation of China(Grant Nos.12074140 and 12034009)+1 种基金the China Postdoctoral Science Foundation(Grant No.2020M681031)the Program for JLU Science and Technology Innovative Research Team(JLUSTIRT)。
文摘Semiconductivity and superconductivity are remarkable quantum phenomena that have immense impact on science and technology,and materials that can be tuned,usually by pressure or doping,to host both types of quantum states are of great fundamental and practical significance.Here we show by first-principles calculations a distinct route for tuning semiconductors into superconductors by diverse large-range elastic shear strains,as demonstrated in exemplary cases of silicon and silicon carbide.Analysis of strain driven evolution of bonding structure,electronic states,lattice vibration,and electron-phonon coupling unveils robust pervading deformation induced mechanisms auspicious for modulating semiconducting and superconducting states under versatile material conditions.This finding opens vast untapped structural configurations for rational exploration of tunable emergence and transition of these intricate quantum phenomena in a broad range of materials.
基金the National Key Research and Development Program of China(Grant No.2018YFA0703400)the National Natural Science Foundation of China(Grant Nos.11704044 and 11974134)+1 种基金the Jilin Province Outstanding Young Talents Project(Grant No.20190103040JH)the China Postdoctoral Science Foundation(Grant No.2018M631870)。
文摘Gallium arsenide(GaAs),a typical covalent semiconductor,is widely used in the electronic industry,owing to its superior electron transport properties.However,its brittle nature is a drawback that has so far significantly limited its application.An exploration of the structural deformation modes of GaAs under large strain at the atomic level,and the formulation of strategies to enhance its mechanical properties is highly desirable.The stressstrain relations and deformation modes of single-crystal and nanotwinned GaAs under various loading conditions are systematically investigated,using first-principles calculations.Our results show that the ideal strengths of nanotwinned GaAs are 14% and 15% higher than that of single-crystal GaAs under pure and indentation shear strains,respectively,without producing a significantly negative effect in terms of its electronic performance.The enhancement in strength stems from the rearrangement of directional covalent bonds at the twin boundary.Our results offer a fundamental understanding of the mechanical properties of single crystal GaAs,and provide insights into the strengthening mechanism of nanotwinned GaAs,which could prove highly beneficial in terms of developing reliable electronic devices.
基金supported by the National Natural Science Foundation of China(12004252,52272265,U1932217,11974246,52072400,52025025,and 92065109)the National Key R&D Program of China(2018YFA0704300,2021YFA1401800,2018YFE0202601,2020YFA0308800,and 2022YFA1403400)+2 种基金Shanghai Science and Technology Plan(21DZ2260400)Beijing Natural Science Foundation(Z190010,Z210006,and Z190006)the support from the Analytical Instrumentation Center(#SPST-AIC10112914),School of Physical Science and Technology(SPST),ShanghaiTech University。
