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Experimental Methods for Trapping Ions Using Microfabricated Surface Ion Traps
Published on: August 17, 2017
Long-lived spin coherence in silicon with an electrical spin trap readout
G W Morley1, D R McCamey, H A Seipel
1London Centre for Nanotechnology and Department of Physics and Astronomy, University College London, London WC1H 0AH, United Kingdom.
Physical Review Letters
|December 31, 2008
Summary
Researchers achieved long spin coherence times in silicon using pulsed electrically detected magnetic resonance. This method enhances spin-to-charge conversion, enabling electrical detection of spin coherence exceeding 100 microseconds.
Area of Science:
- Solid-state physics
- Quantum information science
- Materials science
Background:
- Electrically detected magnetic resonance (EDMR) is crucial for probing spin properties in semiconductors.
- Achieving long spin coherence times is essential for quantum computing applications.
Purpose of the Study:
- To present pulsed electrically detected magnetic resonance (EDMR) of phosphorous-31 (31P) in silicon.
- To investigate spin-to-charge conversion mechanisms for enhanced spin coherence detection.
Main Methods:
- Utilized pulsed EDMR on 31P in bulk crystalline silicon.
- Operated at very high magnetic fields (B0 > 8.5 T) and low temperatures (T = 2.8 K).
- Employed highly polarized conduction electrons and 31P donor electrons (>95% polarization).
Main Results:
- Demonstrated that spin-dependent electron capture and reemission by 31P donors cause minimal decoherence.
- Achieved electrical detection of spin coherence times exceeding 100 microseconds (µs).
- Observed a 50-fold increase in detected spin coherence time compared to previous EDMR experiments.
Conclusions:
- The presented spin-to-charge conversion mechanism offers superior performance for EDMR.
- This advancement significantly extends the capabilities of electrical spin readout in silicon.
- Opens new avenues for sensitive spin measurements and quantum technologies.
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