Prediction of high-Tc superconductivity in two corrugated graphene sheets with intercalated CeH9 molecules

TL;DR

This paper predicts a high-temperature superconductivity transition at nearly 199 K in a graphene-based system doped with CeH9 molecules at ambient pressure, using variational calculations to identify optimal molecular distributions.

Contribution

It introduces a novel low-pressure superconductivity prediction in a graphene-CeH9 system, with specific molecular arrangements leading to high critical temperatures.

Findings

Superconductivity predicted at Tc = 198.61 K without external pressure.

Optimal CeH9 distribution closely matches graphene corrugation periodicity.

High critical current density of approximately 10^7 A/cm^2.

Abstract

Recent discoveries involving high-temperature superconductivity in H3S and LaH10 have sparked a renewed interest in exploring the potential for superconductivity within hydrides. These superconductors require extremely high-pressure condition ( 100 GP a), rendering them virtually impractical for industrial applications. In this study, we verify the occurrence of a low pressure superconductivity phase transition in a system containing two graphene layers with sine form corrugations where CeH9 doped molecules are intercalated between the layers. The lowest-order constrained variational method is applied to calculate the thermodynamic and electrical properties of the valence electrons. We examine 9900 different distributions of CeH9 molecules separately for finding a second-order phase transition with maximized critical temperature. The novelty of the present work is the prediction of a superconductivity transition at Tc = 198.61 K for a specific distribution of CeH9 molecules with applying no external pressure on the exterior surfaces of the graphene sheets. Notably, this critical temperature is approximately 65 K higher than that observed in cuprate materials (HgBa2Ca2Cu3O8+{\delta}), which are known for their high Tc values at room pressure. It is interesting that in this particular case, the distribution periodicity of CeH9 molecules bears the closest resemblance to the periodicity of the graphene corrugations among all 9900 examined cases. Computing the energy gap of the valence electrons reveals that this critical behavior corresponds to an unconventional superconductivity phase transition exhibiting a high critical current density on the order of 107 A/cm2