First-Principles Study On The Electronic Structure Of Fese Under Pressure

Abstract

This Work Focuses On The Study Of The Band Structure And Super Conductivity Of Fe Se Under Pressure(Varying Atomic Position). We Have Performed Density Functional Theory(Dft) Calculations As Implemented In Quantum Espressoto Calculate The Electronic Structure Of The Iron-Based Superconductor Iron-Selenium (Fese). In Our Study, We Have Performed A Comprehensive Set Of Calculations Involving How Pressure Influences On The Electronic Structure And The Lattice Dynamics Properties Of Fese. All Calculations Were Executed Using The Tetragonal Lead-Oxide Or P4/Nmm Structure, With Lattice Parametersa And C, Various Volumes And C/A Ratios, And Found Superconducting Transitiontemperature Of Fese(Tc) Increases Sensitively Under Pressure From 8kto 16.75k At P = 2kbar, Furthermore, We Investigated Fermi Energy, Total Energies And Pressure At Ground State By Using A Pseudopotential Method. We Obtained Comparable Results With Experimental In Both Calculations. Super Conductingcritical Temperature Tc Were Calculated By Using Our Dos Resultin The Mcmillan Formalism Under Pressure, Our Results Show That The Super Conductivity Critical Temperature Continues To Rise. We Also Found That The Equilibrium Configuration Of Fese In The Tetrahedral Structure To Have A Volume Of 75.49[A?? 3] And 77.557[A?? 3] With C/A Ratio Of 1.4889 And 1.552 In Scf And Optimization Respectively. Thus Obtained Results Are Comparable To The Experiment Alvalue (C:a = 1.47[A.U], V = 78.219[A?? 3]. The Density?��?S At The Fermi Energy Are Slightly Enhanced Under Pressure. Zero Pressure Values Of Dos At Ef Are2.69(State/Cell/Ev). At Pressures Corresponding To The Maximum Critical Temperature , The Density?��?S Equal To 3.54(State/Cell/Ev) (P = 2kbar).