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arXiv · 2204.07453

Quantum control of hole spin qubits in double quantum dots

D. Fernandez-Fernandez·Y. Ban·G. Platero
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Abstract

Hole spin qubits in semiconductor quantum dots (QDs) are promising candidates for quantum information processing due to their weak hyperfine coupling to nuclear spins, and to the strong spin-orbit coupling which allows for rapid operation time. We propose a coherent control on two heavy-hole spin qubits in a double QD by a fast adiabatic driving protocol, which helps to achieve higher fidelities than other experimentally commonly used protocols as linear ramping, $π$-pulses or Landau-Zener passages. Using fast quasiadiabatic driving via spin-orbit coupling, it is possible to reduce charge noise significantly for qubit manipulation and achieve high robustness for the qubit initialization. We also implement one and two-qubit gates, in particular, NOT, CNOT, and SWAP-like gates, of hole spins in a double QD achieving fidelities above $99\%$, exhibiting the capability of hole spins to implement universal gates for quantum computing.

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D. Fernandez-Fernandez, Y. Ban, G. Platero. 2022-10-27. Quantum control of hole spin qubits in double quantum dots. https://doi.org/10.1103/physrevapplied.18.054090

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