Coupling between a Si/SiGe Resonant Exchange Qubit and a High-Impedance Microwave Resonator

Area of Science:

• Quantum Computing
• Solid-State Physics
• Quantum Information Science

Background:

• Coherent spin-photon coupling is crucial for silicon-based quantum computation.
• Resonant exchange (RX) qubits in triple quantum dots offer potential for qubit scaling and electrical control.

Purpose of the Study:

• To experimentally demonstrate strong coupling between silicon RX qubits and microwave photons.
• To investigate the decoherence mechanisms in silicon RX qubits.

Main Methods:

• Fabrication of a Si/SiGe heterostructure with a triple quantum dot.
• Measurement of spin-photon coupling strength and decoherence rates.
• Analysis of decoherence dependence on detuning using a phenomenological model.

Main Results:

• Achieved strong coupling between an RX qubit and a high-impedance resonator with coupling strength g_{s}/(2π)=65.8 MHz.
• Measured a decoherence rate γ_{s}/(2π)=21.4 MHz.
• Identified charge noise as the primary source of decoherence.

Conclusions:

• Demonstrated the viability of RX qubits in silicon for quantum computation.
• Highlighted the importance of RX qubits for large-scale integration in silicon quantum processors.
• Opened new avenues for developing quantum networks based on silicon.