Scaling NbTiN-based ac-powered Josephson digital to 400M devices/cm${}^2$

Anna Herr, Quentin Herr, Steve Brebels +9

We describe a fabrication stackup for digital logic with 16 superconducting NbTiN layers, self-shunted a-silicon barrier Josephson Junctions (JJs), and low loss, high-$\kappa$ tunable H…