Towards a silicon-based eight-qubit cloud quantum computer

Quantum Inspire is a cloud platform giving public access to quantum computers based on superconducting and semiconducting qubits. The semiconductor quantum processor is an eight-qubit device based on electron spins in silicon. We electrostatically define a linear array of eight quantum dots on low-disorder ²⁸Si/SiGe heterostructures (1-3). We utilize a Pauli spin blockade (PSB)-readout using two additional charge sensors, a micromagnet-enabled electric-dipole spin resonance (EDSR) for single-qubit gates, and a two-qubit controlled-phase (CZ) gate. We perform automated calibrations ranging from tuning the charge sensor to compensating for qubit crosstalk—necessary for keeping our spin-qubit processor online. We present the latest results on the functionality and the performance of our system which will be made freely accessible to everyone.

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