A superconducting readout system (300; 400; 500), comprising: a first superconducting flux qubit (301; 401; 501a) including a qubit loop formed of a material that is superconducting below a critical temperature and at least one Josephson junction; a signal input line; a signal output line; a variable transformer circuit comprising a DC-SQUID (331; 431; 531), a primary inductor, and a secondary inductor, wherein the DC-SQUID (331; 431; 531) is communicatively coupleable to the qubit loop of the first superconducting flux qubit (301; 401; 501a), the DC-SQUID (331; 431; 531) and the primary inductor are electrically connected in parallel with one another with respect to the signal input line, the primary inductor and the secondary inductor are positioned sufficiently proximate one another to inductively couple signals therebetween, and the secondary inductor is electrically connected in series with the signal output line, the signal input line operable to route a first fraction of a drive current through the DC-SQUID (331; 431; 531) and a second fraction of the drive current through the primary inductor, the first fraction of the drive current determined at least in part by an effective critical current of the DC-SQUID (331; 431; 531), the primary inductor operable to prevent DC-SQUID (331; 431: 531) from becoming resistive, and a first latching qubit (450; 551a) including a first loop of superconducting material and a compound Josephson junction that interrupts the first loop of superconducting material, the compound Josephson junction comprising a closed loop of superconducting material interrupted by at least two Josephson junctions, wherein the first loop of superconducting material and the compound Josephson junction form a closed superconducting current path, wherein the first loop of superconducting material of the first latching qubit (450; 551a) is communicatively coupleable to the qubit loop of the first superconducting flux qubit (301; 401; 501a) such that the DC-SQUID (331; 431; 531) is communicatively coupleable to the qubit loop of the first superconducting flux qubit (301; 401; 501a) via the first latching qubit (450; 551a), and wherein the first latching qubit (450; 551a) is communicatively coupleable to the first superconducting flux qubit (301; 401; 501a) via galvanic coupling or inductive coupling. a first superconducting flux qubit (301; 401; 501a) including a qubit loop formed of a material that is superconducting below a critical temperature and at least one Josephson junction; a signal input line; a signal output line; a variable transformer circuit comprising a DC-SQUID (331; 431; 531), a primary inductor, and a secondary inductor, wherein the DC-SQUID (331; 431; 531) is communicatively coupleable to the qubit loop of the first superconducting flux qubit (301; 401; 501a), the DC-SQUID (331; 431; 531) and the primary inductor are electrically connected in parallel with one another with respect to the signal input line, the primary inductor and the secondary inductor are positioned sufficiently proximate one another to inductively couple signals therebetween, and the secondary inductor is electrically connected in series with the signal output line, the signal input line operable to route a first fraction of a drive current through the DC-SQUID (331; 431; 531) and a second fraction of the drive current through the primary inductor, the first fraction of the drive current determined at least in part by an effective critical current of the DC-SQUID (331; 431; 531), the primary inductor operable to prevent DC-SQUID (331; 431: 531) from becoming resistive, and a first latching qubit (450; 551a) including a first loop of superconducting material and a compound Josephson junction that interrupts the first loop of superconducting material, the compound Josephson junction comprising a closed loop of superconducting material interrupted by at least two Josephson junctions, wherein the first loop of superconducting material and the compound Josephson junction form a closed superconducting current path,