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Superconductivity of Light-Elements Doped H$ {}_{3} $S

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 نشر من قبل Hongyi Guan
 تاريخ النشر 2021
  مجال البحث فيزياء
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Pressurized hydrogen-rich compounds, which could be viewed as precompressed metallic hydrogen, exhibit high superconductivity, thereby providing a viable route toward the discovery of high-temperature superconductors. Of particular interest is to search for high-temperature superconductors with low stable pressure in terms of pressure-stabilized hydrides. In this work, with the aim of obtaining high-temperature superconducting compounds at low pressure, we attempt to study the doping effects for high-temperature superconductive $ mathrm{H_3S} $ with supercells up to 64 atoms using first principle electronic structure simulations. As a result of various doping, we found that Na doping for $ mathrm{H_3S} $ could lower the dynamically stable pressure by 40 GPa. The results also indicate P doping could enhance the superconductivity of $ mathrm{H_3S} $ system, which is in agreement with previous calculations. Moreover, our work proposed an approach that could reasonably estimate the superconducting critical temperature ($ T_{c} $) of a compound containing a large number of atoms, saving the computational cost significantly for large-scale elements-doping superconductivity simulations.



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