Electron-phonon coupling strength from <i>ab initio</i> frozen-phonon approach
Yang Sun, Feng Zhang, Cai‐Zhuang Wang, Kai‐Ming Ho, I. I. Mazin, Vladimir Antropov
Abstract
We propose a fast method for high-throughput screening of potential superconducting materials. The method is based on calculating metallic screening of zone-center phonon modes, which provides an accurate estimate for the electron-phonon coupling strength. This method is complementary to the recently proposed rigid muffin tin (RMT) method, which amounts to integrating the electron-phonon coupling over the entire Brillouin zone (as opposed to the zone center), but in a relatively inferior approximation. We illustrate the use of this method by applying it to ${\mathrm{MgB}}_{\text{2}}$, where the high-temperature superconductivity is known to be driven largely by the zone-center modes, and compare it to a sister compound ${\mathrm{AlB}}_{\text{2}}$. We further illustrate the usage of this descriptor by screening a large number of binary hydrides, for which accurate first-principle calculations of electron-phonon coupling have been recently published. Together with the RMT descriptor, this method opens a way to perform initial high-throughput screening in search of conventional superconductors via machine learning or data mining.