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A generalized quantum search algorithm, where phase inversions for the marked state and the prepared state are replaced by π/2 phase rotations, is realized in a 2-qubit NMR heteronuclear system. The quantum algorithm searches a marked state with a smaller step compared to standard Grover algorithm. Phase matching requirement in quantum searching is demonstrated by comparing it with another generalized algorithm where the two phase rotations are π/2 and 3π/2 respectively. Pulse sequences which include non 90 1

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Three chemical vapor deposited diamond films were studied by dynamic nuclear polarization (DNP)-enhanced high-resolution solid-state ~~C nuclear magnetic resonance (NMR) spectroscopy. Enhanced ~3C direct-polarization speetra of diamond filrns were obtained by irradiating the samples with microwaves at or near electron spin resonance Larmor frequency of carbon center free radicals. No NMR signal for sp 2 hybridized carbons could be observed. From the curve of the DNP enhancementas a function of frequency, it is found that the dominant DNP mechanism is the solid-state effect. The ~3C cross-polarization spectrum, which is an evidence for existence of the proton defect in the lattice of diamond films, is much broader than the ~3C single pulse spectrum. The reason is discussed shortly.