Anatoly Dementyev

Dynamic Nuclear Polarization in Silicon Microparticles

We report record high 29Si spin polarization obtained using dynamic nuclear polarization in microcrystalline silicon powder. Unpaired electrons in this silicon powder are due to dangling bonds in the amorphous region of this intrinsically heterogeneous sample. 29Si nuclei in the amorphous region become polarized by forced electron-nuclear spin flips driven by off-resonant microwave radiation while nuclei in the crystalline region are polarized by spin diffusion across crystalline boundaries. Hyperpolarized silicon microparticles have long T1 relaxation times and could be used as tracers for magnetic resonance imaging.

Rapid diffusion of dipolar order enhances dynamic nuclear polarization

We have observed that the bulk proton dipolar reservoir is cooled to a spin temperature of

High-field Overhauser dynamic nuclear polarization in silicon below the metal–insulator transition

15.5\phantom{\rule{0.3em}{0ex}}\ensuremath{\mu}\mathrm{K}

Dynamic nuclear polarization in silicon

in a dynamic nuclear polarization (DNP) experiment, following microwave irradiation for

title

800\phantom{\rule{0.3em}{0ex}}\mathrm{s}

Dynamic nuclear polarization in intermediately-doped single crystal silicon

. This is significantly cooler than the

A Novel Method to Create Multielectron Bubbles

35\phantom{\rule{0.3em}{0ex}}\mathrm{mK}

Generating Spin Echoes with Pi-Pulses: More is Different

spin temperature of the proton Zeeman reservoir following DNP. Equilibration of the two reservoirs results in a 50% increase in the NMR signal intensity, corresponding to a proton Zeeman spin temperature of

Generating Spin Echoes in Dipolar Solids with

23\phantom{\rule{0.3em}{0ex}}\mathrm{mK}

\pi

. In order to achieve this polarization directly, it was necessary to irradiate the sample with microwaves for