earticle

영어

Theoretical calculation of superconducting state parameters (SSPs) like electron-phonon coupling strength ( 𝜆 ), Coulomb pseudopotential (𝜇∗), transition temperature (𝑇𝐶), effective interaction strength (𝑁0𝑉) and isotopic effect parameter (α𝐼) of alkali metals Li and Na have been carried out in the framework of pseudopotential theory. Presently computed SSPs are found to be in good agreement with other reported results. Further, the dependence of SSPs on pressure and hence compressed volume has also been investigated by including the volume dependence of Fermi momentum (𝑘𝐹), Debye temperature (𝜃𝐷) and phonon frequency. It is found that 𝜇∗very feebly depends on compression in volume. The compressed volume at which Coulomb repulsion and attractive electron–phonon interaction are equal is known as critical volume and the corresponding pressure is known as critical pressure. At critical volume, transition temperature and effective interaction strength become zero. It is observed that the results of critical volume predicted by different approaches are in good agreement.