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Updated: Jul 4, 2025
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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
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Strong coupling between a microwave photon and a singlet-triplet qubit
J H Ungerer1,2, A Pally3, A Kononov4
1Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056, Basel, Switzerland. jungerer@g.harvard.edu.
Nature Communications
|February 5, 2024
Summary
We achieved strong coupling between a spin qubit and a superconducting resonator. This quantum information advance uses a novel nanowire quantum dot and resonator integration, exceeding previous weak coupling limits.
Area of Science:
- Quantum Information Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Superconducting resonators and quantum dots are crucial for quantum information processing.
- Previous attempts to couple resonators to spin qubits resulted in weak spin-photon coupling.
Purpose of the Study:
- To achieve strong coupling between a spin qubit and a superconducting resonator.
- To explore quantum information applications using integrated nanowire quantum dots.
Main Methods:
- Integration of a zincblende InAs nanowire double quantum dot with strong spin-orbit interaction into a high-quality resonator.
- Utilizing deterministically grown wurtzite tunnel barriers for quantum confinement.
- Experiments on even charge parity states at large magnetic fields.
Main Results:
- Observed an anti-crossing between the resonator mode and a singlet-triplet qubit.
- Measured a spin-photon coupling strength of g/2π = 139 ± 4 MHz.
- Achieved strong coupling regime, with coupling exceeding resonator decay and qubit dephasing rates.
Conclusions:
- The integrated system demonstrates a significant advancement in spin-photon coupling for quantum information.
- This work paves the way for enhanced quantum computing and communication technologies.
- The magnetic-field resilient design offers robustness for practical quantum applications.
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