A hole spin qubit in a fin field-effect transistor above 4 kelvin

The greatest challenge in quantum computing is achieving scalability. Classical computing, which previously faced such issues, currently relies on silicon chips hosting billions of fin field-effect transistors. These devices are small enough for quantum applications: at low temperatures, an electron or hole trapped under the gate can serve as a spin qubit. Such an approach potentially allows the quantum hardware and its classical control electronics to be integrated on the same chip. However, this requires qubit operation at temperatures above 1 K, where the cooling overcomes heat dissipation. Here we show that silicon fin field-effect transistors can host spin qubits operating above 4 K. We achieve fast electrical control of hole spins with driving frequencies up to 150 MHz, single-qubit gate fidelities at the fault-tolerance threshold and a Rabi-oscillation quality factor greater than 87. Our devices feature both industry compatibility and quality, and are fabricated in a flexible and agile way that should accelerate further development.
Fin-shaped transistors can host hole spin qubits at high enough temperatures to potentially enable the scaling and development of quantum computing systems controlled by conventional electronics co-integrated in the same package.