Gate-based single-shot readout of spins in silicon

Understand

Electron spins in silicon quantum dots provide a promising route towards realising the large number of coupled qubits required for a useful quantum processor.

• At present, the requisite single-shot spin qubit measurements are performed using on-chip charge sensors, capacitively coupled to the quantum dots.
• However, as the number of qubits is increased, this approach becomes impractical due to the footprint and complexity of the charge sensors, combined with the required proximity to the quantum dots.
• Alternatively, the spin state can be measured directly by detecting the complex impedance of spin-dependent electron tunnelling between quantum dots.