  We analyze a system of fermionic $^{6}$Li atoms in an optical trap, and show
that an atom "on demand" can be prepared with ultra-high fidelity, exceeding
0.99998. This process can be scaled to many sites in parallel, providing a
realistic method to initialize N qubits at ultra-high fidelity for quantum
computing. We also show how efficient quantum gate operation can be implemented
in this system, and how spatially resolved single-atom detection can be
performed.
