US Patent 8055318 Superconducting integrated circuit technology using iron-arsenic compounds

A new family of superconducting materials with critical temperature up to 55 K have recently been discovered, comprising a crystal structure with atomic layers of iron and arsenic alternating with atomic layers of rare-earth oxide or alkaline earth. The present invention identifies structures for integrated circuit elements (including Josephson junctions) in these and related materials. These superconducting circuit elements will operate at a higher temperature than low-temperature superconductors such as niobium, and may be easier to manufacture than prior-art high-temperature superconductors based on copper-oxides.