  Selective coherence control and electrically mediated exchange coupling of
single electron spin between triplet and singlet states using numerically
derived optimal control of proton pulses is demonstrated. We obtained spatial
confinement below size of the Bohr radius for proton spin chain FWHM. Precise
manipulation of individual spins and polarization of electron spin states are
analyzed via proton induced emission and controlled population of energy shells
in pure 29Si nanocrystal. Entangled quantum states of channeled proton
trajectories are mapped in transverse and angular phase space of 29Si axial
channel alignment in order to avoid transversal excitations. Proton density and
proton energy as impact parameter functions are characterized in single
particle density matrix via discretization of diagonal and nearest off-diagonal
elements. We combined high field and low densities (1 MeV/92 nm) to create
inseparable quantum state by superimposing the hyperpolarizationed proton spin
chain with electron spin of 29Si. Quantum discretization of density of states
(DOS) was performed by the Monte Carlo simulation method using numerical
solutions of proton equations of motion. Distribution of gaussian coherent
states is obtained by continuous modulation of individual spin phase and
amplitude. Obtained results allow precise engineering and faithful mapping of
spin states. This would provide the effective quantum key distribution (QKD)
and transmission of quantum information over remote distances between quantum
memory centers for scalable quantum communication network. Furthermore,
obtained results give insights in application of channeled protons subatomic
microscopy as a complete versatile scanning-probe system capable of both
quantum engineering of charged particle states and characterization of quantum
states below diffraction limit linear and in-depth resolution.
