8.5 GHz Qubit Controller

The SHFQC+ Qubit Controller can control, read out and provide fast feedback on up to 6 superconducting qubits. It integrates the functionality of the SHFQA+ Quantum Analyzer, the SHFSG+ Signal Generator and more in a single instrument. With integrated microwave generation, a trigger distribution unit and the ultrafast feedback of 350 ns between all channels, simple microwave connections between the SHFQC+ and a cryostat are sufficient to start advanced qubit measurements. To provide flexibility for systems with a small number of qubits, the SHFQC+ comes in three possible configurations, in which either 2, 4, or 6 of the signal generator channels are enabled. For the 2- and 4-channel configurations, additional signal generator channels can be enabled in the field. As a result, the setup is fully software-controlled and can be reconfigured as needed to match the experimental requirements.

Each control channel of the SHFQC+ has its own powerful sequencer for creating phase- and timing-programmable waveforms, so that a single SHFQC+ can control or couple qubits with pulses from DC to 8.5 GHz, and react at any time on measurements from the readout channel. With the SHFQC-16W upgrade option, the readout channel's freely configurable integration weights and readout-pulse memories are doubled from 8 to 16. This provides more flexibility in configuring the readout, e.g. by enabling full real-time control and readout of 6 qutrits.

Advanced features such as a real-time oscilloscope, fast spectroscopy, and the pulse-level sequencing capability allow users to further speed up their system tune-up and measurements.

The SHFQC+ integrates into the Zurich Instruments Quantum Computing Control System (QCCS) and is intuitively operated through the LabOne Q Software. This enables a seamless combination with other instruments such as the HDAWG for fast flux or gate voltage signals up to 750 MHz. Within a larger QCCS, the SHFQC+ enables access to fast local and global feedback as well as to error correction protocols for 100 qubits and beyond.