International Business Machines Corporation
Junction fabrication method for forming qubits

Abstract:

A method of making a Josephson junction for a superconducting qubit includes providing a substructure having a surface with first and second trenches perpendicular to each other defined therein. The method further includes evaporating a first superconducting material to deposit the first superconducting material and evaporating a second superconducting material to deposit the second superconducting material in the first trench to provide a first lead, and forming an oxidized layer on the first and second superconducting materials. The method includes evaporating a third superconducting material at an angle substantially perpendicular to the surface of the substructure to deposit the third superconducting material in the second trench without rotating the substructure to form a second lead. A vertical Josephson junction is formed at the intersection of the first and second trenches electrically connected through the first lead and through the second lead.