Alkaline-Earth-Metal Atoms as Few-Qubit Quantum Registers

We propose and analyze a novel approach to quantum information processing, in
which multiple qubits can be encoded and manipulated using electronic and
nuclear degrees of freedom associated with individual alkaline-earth atoms
trapped in an optical lattice. Specifically, we describe how the qubits within
each register can be individually manipulated and measured with sub-wavelength
optical resolution. We also show how such few-qubit registers can be coupled to
each other in optical superlattices via conditional tunneling to form a
scalable quantum network. Finally, potential applications to quantum
computation and precision measurements are discussed.