High-temperature conventional superconductivity in the boron-carbon system: material trends

In this paper, we probe the possibility of high-temperature conventional superconductivity in the boron-carbon system, using ab initio screening. A database of 320 metastable structures with fixed composition (50%/50%) is generated with the minima hopping method, and characterized with electronic and vibrational descriptors. Full electron-phonon calculations on 16 representative structures allow us to identify general trends in Tc across and within the four families in the energy landscape, and to construct an approximate Tc predictor, based on transparently interpretable and easily computable electronic and vibrational descriptors. Based on these, we estimate that around 10% of all metallic structures should exhibit Tc's above 30 K. This paper is a first step toward ab initio design of new high-Tc superconductors.