Superconducting properties and vortex avalanches of high entropy and medium entropy alloys synthesized by melting and powder metallurgical processes

High-entropy alloys (HEA) are the compounds with multi-component mixing of elements with high symmetry crystalline structures such as cubic (FCC and BCC) or hexagonal close packed (HCP) phase. HEAs possess outstanding structural and physical properties including high thermal stability with excellent hardness and high corrosion and wear resistances. HEA superconductors are known to be conventional type-II s−wave superconductors. We investigated the superconducting properties of high entropy and medium entropy alloys with various synthesis methods such as arc-melting, hot press, and spark plasma sintering methods. The superconducting properties are significantly different depending on the synthesis methods. Here we overview the superconducting properties of high entropy and medium entropy alloys such as strong and weak coupling, vortex avalanches, strong flux pinning, and unconventional vortex dynamics with synthesis methods.