Recently, hole spins in silicon and germanium have shown increasing interest for quantum information processing owing to the advantage of manipulating their state with electric instead of magnetic microwave fields [1,2]. This is possible due to the strong spin-orbit interaction intrinsically present in the valance band of these materials. Spin-orbit coupling should as well offer the possibility to couple a hole spin to the electric field component of a microwave photon.
Here we show a strong hole spin-photon interaction on a CMOS compatible platform. We find a coupling strength of 300 MHz, exceeding the spin decoherence rate and the photon decay rate by a factor 27. Our coupling largely exceeds the best figures reported so far in the case of electrons in silicon [3, 4], opening the door to the achievement of high-fidelity two qubits gate with distant spins.
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