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Dressed-state resonant coupling between bright and dark spins in diamond
C Belthangady1, N Bar-Gill1, L M Pham2
1Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA and Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
Physical Review Letters
|August 29, 2014
Summary
Researchers coupled bright nitrogen-vacancy (NV) spins to dark substitutional-nitrogen (P1) spins using oscillating magnetic fields. This technique transfers spin polarization and could cool dark spins for quantum applications.
Area of Science:
- Quantum physics
- Solid-state spin systems
- Optically active defects
Background:
- Spin impurities in solids are typically optically inactive ('dark') at room temperature.
- Nitrogen-vacancy (NV) centers in diamond are an exception, exhibiting optically controllable ('bright') spin states.
- NV centers allow optical pumping, spin manipulation, and readout at room temperature.
Purpose of the Study:
- To demonstrate a method for coupling optically bright NV electronic spins to optically dark substitutional-nitrogen (P1) electronic spins.
- To enable spin polarization transfer from NV centers to P1 spins.
- To explore potential applications in quantum information, sensing, and low-temperature spin bath cooling.
Main Methods:
- Utilizing resonant coupling by dressing spin states with oscillating magnetic fields.
- Implementing a scheme to link NV electronic spins with nearby P1 electronic spins.
- Leveraging the optical properties of NV centers to influence P1 spins.
Main Results:
- Successfully demonstrated resonant coupling between bright NV spins and dark P1 spins.
- Showcased the transfer of spin polarization from NV to P1 spins.
- Established a mechanism for potential cooling of a mesoscopic bath of dark spins.
Conclusions:
- The demonstrated resonant coupling provides a novel method to control dark spins using bright NV centers.
- This technique offers a pathway to cool dark spin ensembles to near-zero temperatures.
- The findings present a valuable resource for quantum information processing, advanced sensing, and studying quantum many-body systems.
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