We propose a strategy to achieve the Grover search algorithm by adiabatic
passage in a very efficient way. An adiabatic process can be characterized by
the instantaneous eigenvalues of the pertaining Hamiltonian, some of which form
a gap. The key to the efficiency is based on the use of parallel eigenvalues.
This allows us to obtain non-adiabatic losses which are exponentially small,
independently of the number of items in the database in which the search is
performed.Comment: 7 pages, 4 figure