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Geometric spin echo under zero field
Yuhei Sekiguchi1, Yusuke Komura1, Shota Mishima1
1Department of Physics, Electrical and Computer Engineering, Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama 240-8501, Japan.
Nature Communications
|May 20, 2016
Summary
Researchers demonstrate spin echo for degenerate spins using geometric control in diamond, enabling long coherence without magnetic fields. This breakthrough paves the way for advanced quantum memory and biosensing applications.
Area of Science:
- Quantum physics
- Solid-state physics
- Quantum information science
Background:
- Spin echo is crucial for quantum registers and biomedical imaging.
- Strong magnetic fields are traditionally required for effective spin echo control and resolution.
- Degenerate spins are typically uncontrollable in zero magnetic fields.
Purpose of the Study:
- To demonstrate spin echo for a degenerate spin subsystem.
- To explore geometric control mechanisms for degenerate spins.
- To investigate the role of zero-field splitting in spin coherence.
Main Methods:
- Utilized a nitrogen-vacancy (NV) center in diamond.
- Employed geometric control via a mediating state split by crystal field.
- Leveraged zero-field splitting for spin protection.
Main Results:
- Successfully generated spin echo for a degenerate spin subsystem.
- Demonstrated geometric control of degenerate spins without external magnetic fields.
- Showcased that zero-field splitting protects degenerate spins by symmetry breaking.
Conclusions:
- Geometric spin echo under zero field maintains coherence without dynamics.
- This method enables pseudo-static quantum random access memory.
- Opens possibilities for non-invasive biosensors.
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