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High-magnetic fields enhance NMR spectral resolution and sensitivity but also bring new challenges requiring fast sample spinning rate and large bandwidth. I will present solid-state NMR applications using high-fields and technique development addressing these issues.
1. Spinning sideband manipulation based on magic-angle turning (MAT) can obtain ‘infinite-speed’ MAS spectors. Such an experiment can cover anisotropy up to 1MHz as illustrated with paramagnetic Li-ion battery materials and high-Z nuclei in chalcogenide glasses.
2. Multiple-quantum magic-angle spinning (MQMAS) is a widely used experiment for obtaining high-resolution solid state NMR spectra of quadrupolar spins. NMR probes capable of generating strong rf and improved pulse schemes dramatically improve the MQMAS efficiency. The enhancement allows for application to insensitive low- quadrupolar nuclei like 39K and 25Mg in layered double hydroxides and bio-organic solids.
3. Direct observation of 14N is difficult due to large quadrupolar coupling and the spin-1 nucleus. Indirect 14N detection through 13C and 1H under high-resolution magic-angle spinning condition can overcome the difficulties of low sensitivity and broad lines. The indirect experiment based on HMQC allows for the measurement of inter-nuclei distance and 14N electric-field gradient parameters which inaccessible through the conventional 15N NMR.

In 1987 Greenberger, Horne, and Zeilinger realized that the entanglement of more than two particles implies a non-statistical conflict between local realism and quantum mechanics. The resulting predictions were experimentally confirmed by entangling three photons in their polarization. Experimental efforts since have singularly focused on increasing the number of particles entangled, while remaining in a two-dimensional space for each particle. Here we show the experimental generation of the first multi-photon entangled state where both—the number of particles and the number of dimensions—are greater than two. Interestingly, our state exhibits an asymmetric entanglement structure that is only possible when one considers multi-particle entangled states in high dimensions. Two photons in our state reside in a three-dimensional space, while the third lives in two dimensions. Our method relies on combining two pairs of photons, high-dimensionally entangled in their orbital angular momentum, in such a way that information about their origin is erased. Additionally, we show how this state enables a new type of “layered” quantum cryptographic protocol where two parties share an additional layer of secure information over that already shared by all three parties.