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Atomic Resolution Magnetic Resonance Diffraction. Mladen Barbic and Axel Scherer, Dept. of Applied Physics M/S 200-36, California Institute of Technology, Pasadena, CA 91125.

We will present our recent proposal [1] for the observation of sharp spectral peaks in the magnetic resonance signal for the case of a crystal in close proximity of a ferromagnetic nanosphere. The appearance of the peaks is a direct signature of the discrete atomic sites in the crystal lattice, and the positions of the spectral peaks are sensitive to the crystal unit cell size thereby providing a magnetic resonance diffraction method for determination of the basic parameters of the crystal at the atomic scale. Therefore, the technique provides a magnetic resonance alternative to the other three well-known atomic resolution crystallography techniques of x-ray, electron, and neutron diffraction. Applications to the studies of crystals, thin films, and crystallites will be discussed, and potential measurement methods for the confirmation of the diffraction theory will be proposed [2]. The technique significantly relaxes the magnetic resonance sensitivity requirements by allowing many spins to coherently contribute to the signal while still providing atomic scale information. The analysis suggests that the goal of detecting atomic resolution magnetic resonance diffraction [3,4] is well within reach of current experimental techniques such as Magnetic Resonance Force Microscopy [5].

[1] M. Barbic J. Appl. Phys. 91, 9987 (2002).

[2] M. Barbic and A. Scherer J. Appl. Phys. 92, 7345 (2002).

[3] P. Mansfield and P. K. Grannell J. Phys. C: Solid State Phys. 6, L422 (1973).

[4] P. Mansfield and P. K. Grannell Phys. Rev. B 12, 3618 (1975).

[5] Sidles J. A. et al. Rev. Mod. Phys. 67, 249 (1995).