By: Božidar N. Šoškić, Jonas Bekaert, Cem Sevik, and Milorad V. Milošević
Imagine an atomically thin material capable of conducting electricity without resistance, with the potential to revolutionize technology. Enter hydrogenated borophene, also known as ‘borophane’ – a unique two-dimensional form of boron. The name ‘borophane’ combines ‘borophene’ with the suffix ‘-phane,’ commonly used for hydrogenated compounds (as in ‘graphane,’ the hydrogenated form of graphene). The hydrogen atoms stabilize borophene’s crystal structure and alter its electronic properties, making it more resilient to oxidation, hence more suitable for practical applications.
Figure: Structure of borophane, consisting of boron atoms (red spheres) and hydrogen atoms (blue spheres), deposited on a substrate (green spheres), by which carrier doping and strain can be achieved. On top, the superconducting properties are summarized, namely the distribution of the superconducting pairing strength (D) on the characteristic Fermi contours of borophane, and the corresponding critical temperature of 29 K.
Borophene exhibits remarkable physical properties, but hydrogenation elevates these to a whole new level. Hydrogen not only enhances the stability of borophene but also significantly improves its superconducting potential, enabling it to conduct electricity with zero energy loss. The critical temperature is a fundamental property of superconducting materials. It refers to the temperature below which a material exhibits superconductivity. In other words, when a superconducting material is cooled below its critical temperature, it can conduct electricity with no energy loss, unlike normal conductors that lose energy in the form of heat.
Hydrogen plays a pivotal role in elevating the critical temperature of borophene by stabilizing its otherwise inherently unstable structure. This structural stability is essential for preserving borophene’s intrinsic superconducting properties, which would otherwise be lost due to structural collapse. Additionally, hydrogenation enhances borophene’s sensitivity to external factors such as tensile strain and hole doping, both of which can significantly raise its critical temperature. This increased sensitivity stems from hydrogen’s ability to modify the material’s electronic band structure and charge distribution, making it more adaptable to external stimuli. Consequently, its superconducting temperature is pushed to levels where practical, energy-efficient electronics could thrive. This breakthrough paves the way for the development of next-generation ultra-efficient devices powered by borophene-based superconductors.
Solving this complex many-body problem was made possible by the advanced computational resources of the VSC.
To investigate this fascinating superconducting behavior, we carried out a theoretical study of the material’s electronic properties using first-principles calculations rooted in the fundamental principles of quantum mechanics. By incorporating the interaction between electrons and quantum lattice vibrations (phonons), we developed a theoretical framework to explain the emergence of superconductivity. Solving this complex many-body problem was made possible by the advanced computational resources of the VSC.
Read the full article in ACS Publications here