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Entangling gates on degenerate spin qubits dressed by a global field.
Ingvild Hansen1, Amanda E Seedhouse2,3, Santiago Serrano2
1School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, NSW, Australia. ingvild.hansen@ntnu.no.
Nature Communications
|September 3, 2024
Summary
Semiconductor spin qubits offer a path to scalable quantum computing. This study introduces a novel control strategy using global fields and local electrodes to overcome frequency crowding in large quantum processors.
Area of Science:
- Quantum computing
- Semiconductor physics
- Quantum information science
Background:
- Semiconductor spin qubits are a leading platform for quantum computation due to high performance and manufacturability.
- Current qubit control methods using spectral selectivity face scaling challenges like frequency crowding and signal interference.
Purpose of the Study:
- To propose and demonstrate a new qubit control strategy for large-scale quantum processors.
- To overcome the limitations of frequency-based qubit addressing.
Main Methods:
- Utilizing arrays of degenerate spins coherently dressed by a global control field.
- Employing local electrodes for individual qubit addressing.
- Demonstrating simultaneous on-resonance driving of degenerate qubits.
Main Results:
- Achieved simultaneous driving of two degenerate qubits with equal Larmor frequencies.
- Implemented SWAP oscillations during on-resonance driving, demonstrating driven two-qubit gates.
- Showcased enhanced robustness and reduced fragility of entangling gates through dressing.
Conclusions:
- The proposed dressing strategy offers a paradigm shift for qubit control in large-scale quantum computing.
- This method effectively addresses frequency crowding and improves gate fidelity.
- Paves the way for more scalable and robust quantum processors.
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