Figure 1
From: Independent, extensible control of same-frequency superconducting qubits by selective broadcasting
Schematic of independent control of same-frequency qubits using a vector switch matrix (VSM). The device (grey-coloured box on right) connects two transmons with matched frequency (QT and QB: 6.220 GHz) indirectly through coupling buses and a third non-matched transmon (QM: 6.550 GHz). This provides the smallest relevant subunit of the four-frequency surface-code fabric illustrated above right (colours represent distinct qubit frequencies). The VSM (blue box) allows independent, simultaneous transmon control with tailored DRAG pulsing for each qubit through dedicated drive lines. The link between inputs and outputs can be switched on nanosecond timescales using the digital markers MT and MB (orange lines). Gaussian and derivative-of-Gaussian pulses are independently tuned in amplitude and phase for each input–output pair (top left).
