Thermal conductivity and Lorenz ratio of metals at intermediate temperatures with mode-level first-principles analysis

Ultrahigh Electron Thermal Conductivity in T‐Graphene, Biphenylene, and Net‐Graphene

“…The Lorenz ratio L = κ e / σT is generally adopted to estimate the phonon thermal conductivity as κ ph = κ total − LσT in which L is generally assumed to be the Sommerfeld value L 0 = 2.44 × 10 −8 ΩWK −2 . [ 59,70 ] We note that this approximation is inadequate especially at low temperatures ( T ≪ T D , where T D is Debye temperature) since L has large differences compared to L 0 . [ 59 ] Indeed, in the inset of Figure 3b we observe the large deviation between L and L 0 in the 2D carbon allotropes, that is, L < L 0 , indicating that using the Sommerfeld value in this method underestimates (overestimates) κ ph (κ e ).…”

“…[85] They were initially obtained on coarse electron and phonon wave vector grids and then implemented to finer grids using the maximally localized Wannier functions basis as implemented in the el-ph Wannier (EPW) [86,87] to obtain the el-ph scatterings for computing κ e and κ ph . Importantly, an in-house modified EPW code [70,88,89] was used to predict the el-ph coupling scattering rates in order to compute the huge dense k-and q-points more efficiently. The simulation parameters and computational details are provided in Section S3, Supporting Information.…”

Significant Increase of Electron Thermal Conductivity in Dirac Semimetal Beryllonitrene by Doping Beyond Van Hove Singularity

“…[ 63,64 ] To calculate the electron–phonon scattering rates , fine 500 × 500 × 1 k ‐points and 200 × 200 × 1 q ‐points grids were employed. An in‐house modified EPW code [ 35,65,66 ] was used to predict the electron–phonon coupling scattering rates in order to efficiently compute the fine k ‐ and q ‐point grids. Additional simulation details and convergence tests are provided in Sections S2 and S3, Supporting Information, respectively.…”

Four-phonon and electron–phonon scattering effects on thermal properties in two-dimensional 2H-TaS2

“…46 k-Points with 500 × 500 × 1 and q-points with 200 × 200 × 1 were used to compute 1/τ ep ik for κ e , and q-points with 80 × 80 × 1 and kpoints with 500 × 500 × 1 were used to compute 1/τ pe λ for κ ph , using the Wannier interpolation from the coarse grids with 8 × 8 × 1 k-points and 8 × 8 × 1 q-points. An in-house modified EPW code 38,47,48 was used to predict the electron-phonon coupling scattering rates in order to make the computation more efficient.…”