Joint Annual Meeting of the Swiss and Austrian Physical Society 2023

【815】Capacitive crosstalk in gate-based dispersive sensing of spin qubits

8 Sept 2023, 12:45

15m

Room 116

Talk Quantum Computing (by NCCR SPIN) Quantum Computing

Speaker

Alexei Orekhov (IBM Research Zurich)

Description

Dispersive gate sensing, where a resonator is directly attached to a quantum dot gate, is a promising spin qubit readout technique. We discuss a potential limitation of this approach arising from capacitive crosstalk. We find that an ac voltage modulation on a plunger gate of a finFET double quantum dot can induce a 20 times larger signal on the neighboring barrier gate attached to a tank circuit with Qi =1000. The corresponding broadening of the inter-dot charge transition limits the operation of the dots as qubits. We explain this effect by capacitive crosstalk between bondpads and discuss further design constrains that need to be addressed when employing this technique.