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Long-lived electronic spin qubits in single-walled carbon nanotubes
Jia-Shiang Chen1,2, Kasidet Jing Trerayapiwat3, Lei Sun1
1Center for Nanoscale Materials, Argonne National Laboratory, Lemont, IL, 60439, USA.
Nature Communications
|February 15, 2023
Summary
Researchers created highly confined electron spins in single-walled carbon nanotubes (SWCNTs) for quantum computing. These spin qubits exhibit record long coherence times, enabling quantum control operations and paving the way for scalable quantum materials.
Area of Science:
- Quantum computing
- Materials science
- Condensed matter physics
Background:
- Electron spins in solid-state systems are promising for spin-based information processing.
- Single-walled carbon nanotubes (SWCNTs) offer a spin-free environment and weak spin-orbit coupling, ideal for long spin coherence times.
- Disciplined confinement of isolated spins is crucial for implementing spin qubits in SWCNTs.
Purpose of the Study:
- To report the creation of highly confined electron spins in SWCNTs.
- To demonstrate quantum control operations using these electron spins.
- To investigate the decoherence mechanisms and intrinsic coherence times.
Main Methods:
- A bottom-up approach was used to create highly confined electron spins in SWCNTs.
- Coherence time and spin-lattice relaxation time were measured.
- Quantum control operations, such as Rabi oscillations, were performed.
- Decoherence mechanisms were investigated to determine intrinsic coherence times.
Main Results:
- Highly confined electron spins were successfully created in SWCNTs.
- A record long coherence time of 8.2 µs and spin-lattice relaxation time of 13 ms were achieved.
- Quantum control operations, including Rabi oscillations, were demonstrated.
- The intrinsic coherence time was found to be in the tens of milliseconds.
Conclusions:
- Combining molecular approaches with inorganic crystalline systems is a powerful route for reproducible and scalable quantum materials.
- SWCNT-based spin qubits show great potential for qubit applications.
- The demonstrated quantum control and long coherence times highlight the viability of SWCNTs for quantum information processing.
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