Continuously Tunable 2D Gallium-Indium Alloys*

A novel technique for achieving 2D metal layers – Confinement Heteroepitaxy (CHet) [1] – has recently been extended to metallic alloys [2]. We report here the structural energetics, electronic properties, and structural trends in CHet-based Indium/Gallium alloys, identifying trends that may generalize to other 2D metallic alloys that also form continuously tunable alloys. In particular, a rapid reduction in the superconducting transition temperature with increasing indium fraction appears to correlate to the depletion of carrier pockets that participate strongly in the superconductivity of pure 2D Gallium. 

[1] Atomically thin half-van der Waals metals enabled by confinement heteroepitaxy, doi: 10.1038/s41563-020-0631-x

[2] Tunable 2D Group-III Metal Alloys, doi: 10.1002/adma.202104265