  The achievement of three-dimensional atomic resolution magnetic resonance
microscopy remains one of the main challenges in the visualization of
biological molecules. The prospects for single spin microscopy have come
tantalizingly close due to the recent developments in sensitive
instrumentation. Despite the single spin detection capability in systems of
spatially well-isolated spins, the challenge that remains is the creation of
conditions in space where only a single spin is resonant and detected in the
presence of other spins in its natural dense spin environment. We present a
nanomagnetic planar design where a localized Angstrom-scale point in
three-dimensional space is created above the nanostructure with a non-zero
minimum of the magnetic field magnitude. The design thereby represents a
magnetic resonance microscopy lens where potentially only a single spin located
in the focus spot of the structure is resonant. Despite the presence of other
spins in the Angstrom-scale vicinity of the resonant spin, the high gradient
magnetic field of the lens renders those spins inactive in the detection
process.
