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Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
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Fully Tunable Longitudinal Spin-Photon Interactions in Si and Ge Quantum Dots
Stefano Bosco1, Pasquale Scarlino2, Jelena Klinovaja1
1Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland.
Physical Review Letters
|August 26, 2022
Summary
Researchers found a new way to entangle spin qubits in quantum dots using longitudinal spin-photon interactions. This method avoids residual couplings, enabling high-fidelity quantum gates at higher temperatures for scalable quantum computing.
Area of Science:
- Quantum computing
- Solid-state quantum information
Background:
- Spin qubits in silicon and germanium quantum dots are promising for quantum computing.
- Entangling qubits over micrometer distances is a major challenge.
- Current methods using transversal spin-photon interactions cause unwanted qubit couplings and reduce gate fidelity.
Purpose of the Study:
- To overcome the challenge of entangling spin qubits over long distances.
- To investigate longitudinal spin-photon interactions for improved qubit control.
- To develop protocols for high-fidelity, high-temperature two-qubit gates.
Main Methods:
- Investigated hole spin qubits in silicon and germanium quantum dots.
- Analyzed spin-photon interactions, demonstrating tunability from transversal to longitudinal.
- Proposed electrical control and measurement of these interactions.
- Developed protocols for two-qubit entangling gates.
Main Results:
- Demonstrated that longitudinal spin-photon interactions eliminate residual qubit-qubit couplings.
- Showcased naturally emerging, tunable spin-photon interactions in hole spin qubits.
- Proposed protocols for fast, high-fidelity entangling gates.
- Showed protocols are effective at high temperatures.
Conclusions:
- Longitudinal spin-photon interactions offer a path to high-fidelity qubit entanglement.
- Hole spin qubits in quantum dots are a viable platform for scalable quantum processors.
- The proposed methods enable high-temperature operation, advancing quantum computing.
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