Electron-phonon coupling in bcc lithium

Electron-phonon coupling in bcc lithium is studied using a first-principles pseudopotential approach and Wannier-interpolation-based techniques that allow for ultradense sampling of electron-phonon parameters throughout the Brillouin zone. The coupling strength is calculated resolving the fine features of its distribution over the zone, and the contributions to coupling arising from the Fermi surface topology and electron-phonon matrix elements are analyzed separately. We find the value of the electron-phonon coupling constant for pressures in the range of 0--5 GPa to be 0.36--0.43, respectively. We analyze the behavior of the Eliashberg spectral function ${\ensuremath{\alpha}}^{2}F(\ensuremath{\omega})$, estimate the superconducting transition temperature, and compare it with experiment for reasonable values of Coulomb repulsion ${\ensuremath{\mu}}^{*}$.