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Conditional rotation of two strongly coupled semiconductor charge qubits.
Hai-Ou Li1,2, Gang Cao1,2, Guo-Dong Yu2,3
1Key Laboratory of Quantum Information, CAS, University of Science and Technology of China, Hefei, Anhui 230026, China.
Nature Communications
|July 18, 2015
Summary
Researchers demonstrated conditional rotation of two charge qubits in semiconductor quantum dots, achieving high-speed quantum gate operations. This work highlights the potential of charge qubits for scalable quantum computing.
Area of Science:
- Quantum Computing
- Semiconductor Physics
- Quantum Information Science
Background:
- Universal quantum computation relies on single-qubit gates and entangling two-qubit gates.
- Previous two-qubit gate operations in semiconductor quantum dots were limited to electron spin qubits.
Purpose of the Study:
- To demonstrate conditional rotation of two capacitively coupled charge qubits.
- To explore the potential of charge qubits for scalable quantum computing.
Main Methods:
- Utilized GaAs/AlGaAs double quantum dots confining individual electrons.
- Implemented capacitively coupled charge qubits.
- Performed truth table measurements for controlled-NOT operations.
Main Results:
- Achieved gate operations with a clock speed up to 6 GHz due to strong inter-qubit coupling.
- Demonstrated controlled-NOT operations with fidelities comparable to spin-based two-qubit gates.
- Showcased conditional rotation of coupled charge qubits.
Conclusions:
- Semiconductor charge qubits show significant potential for scalable quantum computing.
- The use of long-range Coulomb interaction can stimulate coherent quantum control in other devices.
- This work advances the development of charge qubit-based quantum processors.
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