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Measuring the Spin-Lattice Relaxation Magnetic Field Dependence of Hyperpolarized [1-13C]pyruvate
Published on: September 13, 2019
Controlling spin relaxation with a cavity
A Bienfait1, J J Pla2, Y Kubo1
1Quantronics Group, SPEC, CEA, CNRS, Université Paris-Saclay, CEA-Saclay, 91191 Gif-sur-Yvette, France.
Researchers enhanced spontaneous emission for spins in solids using a superconducting microwave cavity. This significantly boosts spin relaxation rates, enabling on-demand control for quantum information and magnetic resonance applications.
Area of Science:
- Quantum physics
- Solid-state physics
- Cavity quantum electrodynamics
Background:
- Spontaneous emission is a fundamental quantum process for system relaxation.
- Spin relaxation is typically dominated by non-radiative processes due to weak magnetic dipole coupling.
- The Purcell effect demonstrates enhanced spontaneous emission via resonant cavities.
Purpose of the Study:
- To investigate the application of the Purcell effect to spins in solids.
- To achieve spontaneous emission as the dominant spin relaxation mechanism.
- To enable on-demand control of spin relaxation rates.
Main Methods:
- Coupling donor spins in silicon to a high-quality superconducting microwave cavity.
- Tuning spins to the cavity resonance frequency.
- Measuring spin relaxation rates.
Main Results:
- Achieved spontaneous emission as the dominant spin relaxation mechanism for spins in solids.
- Increased spin relaxation rates by three orders of magnitude.
- Demonstrated on-demand control of energy relaxation.
Conclusions:
- Spontaneous emission can be controllably enhanced for spins in solids.
- This technique offers a general method for initializing spin systems.
- Results pave the way for coherent magnetic coupling of spins to microwave photons.
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