Methods and arrangements for driving a quantum mechanical system with cumulative inputs

A method for producing driving signals for a qubit using a driver circuit that comprises:

• a first Josephson junction or first array of Josephson junctions, named the first junction below, the first junction having a first critical current,
• a second Josephson junction or second array of Josephson junctions, named the second junction below, the second junction having a second critical current,
• an inductive path connecting a first side of the first junction to a first side of the second junction, and
• ground connections connecting respective second sides of the first junction and the second junction to a fixed reference potential;
• wherein said first and second critical currents differ from each other by a predefined offset, and wherein the method comprises:
• providing two components of a first differential clock signal to the driver circuit simultaneously through respective two inductors, one coupled to a first half of said first junction and the other coupled to a first half of said second junction,
• providing pulsating data signals to a data input at an intermediate point of said inductive path, and
• conducting pulsating output signals towards said qubit through a pulse output at said intermediate point.