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Updated: Apr 25, 2026
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Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
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Microwave down-conversion with an impedance-matched Λ system in driven circuit QED
K Inomata1, K Koshino2, Z R Lin1
1RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama 351-0198, Japan.
Physical Review Letters
|August 23, 2014
Summary
We demonstrate a new quantum system that uses microwave photons to control qubit states with high fidelity. This breakthrough enables deterministic quantum gates and scalable quantum networks.
Area of Science:
- Quantum Computing
- Quantum Optics
- Solid-State Physics
Background:
- Dispersively coupled qubit-resonator systems are crucial for quantum information processing.
- Λ systems with identical decay rates offer unique control possibilities.
- Interaction with semi-infinite waveguides enables deterministic photon-qubit interactions.
Purpose of the Study:
- To realize an impedance-matched Λ system for deterministic photon-induced Raman transitions.
- To experimentally verify the predicted state switching and photon-qubit interaction.
- To explore applications in quantum gates and scalable quantum networks.
Main Methods:
- Driving a dispersively coupled qubit-resonator system.
- Utilizing a semi-infinite waveguide for photon interaction.
- Measuring microwave response to a continuous probe field.
Main Results:
- Achieved near-perfect (99.7%) extinction of reflection, confirming impedance matching.
- Demonstrated highly efficient (74%) frequency down-conversion.
- Confirmed deterministic Raman transitions and electronic state switching.
Conclusions:
- The developed system enables deterministic quantum gates between material qubits and microwave photons.
- This work paves the way for scalable quantum networks interconnected with waveguide photons.
- The findings represent a significant step towards practical quantum communication and computation.
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