The influence of the electric field created by a gate potential of the
silicon quantum computer on the hyperfine interaction constant (HIC) is
obtained. The errors due to technological inaccuracy of location of donor atoms
under a gate are evaluated. The energy spectra of electron-nuclear spin system
of two interacting donor atoms with various values of HIC are calculated. The
presence of two pairs of anticrossing levels in the ground electronic state is
shown. Parameters of the structure at which errors rate can be greatly
minimized are found.Comment: 12 pages,, 3 figure