Nuclear double resonance between statistical spin polarizations.
We demonstrate nuclear double resonance for nanometer-scale volumes of spins where random fluctuations rather than Boltzmann polarization dominate. When the Hartmann-Hahn condition is met in a cross-polarization experiment, flip-flops occur between two species of spins and their fluctuations become coupled. We use magnetic resonance force microscopy to measure this effect between 1H and 13C spins in 13C-enriched stearic acid. The development of a cross-polarization technique for statistical ensembles adds an important tool for generating chemical contrast in nanometer-scale magnetic resonance.
Poggio
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IBM Research Division, Almaden Research Center, 650 Harry Road, San Jose, California 95120, USA.
Mamin
H J
HJ
Degen
C L
CL
Sherwood
M H
MH
Rugar
D
D