Eur. Phys. J. D 65, 207-217 (2011)
https://doi.org/10.1140/epjd/e2011-20095-2

Regular Article

State-dependent lattices for quantum computing with alkaline-earth-metal atoms

¹ Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, 6020 Innsbruck, Austria
² Institute for Theoretical Physics, University of Innsbruck, 6020 Innsbruck, Austria
³ Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, USA
⁴ JILA, National Institute of Standards and Technology and University of Colorado and Department of Physics, University of Colorado, Boulder, CO 80309-0440, USA

^a e-mail: adaley@pitt.edu

Received: 7 February 2011
Received in final form: 17 May 2011
Published online: 29 July 2011

Abstract

Recent experimental progress with Alkaline-Earth atoms has opened the door to quantum computing schemes in which qubits are encoded in long-lived nuclear spin states, and the metastable electronic states of these species are used for manipulation and readout of the qubits. Here we discuss a variant of these schemes, in which gate operations are performed in nuclear-spin-dependent optical lattices, formed by near-resonant coupling to the metastable excited state. This provides an alternative to a previous scheme [Phys. Rev. Lett. 101, 170504 (2008)], which involved independent lattices for different electronic states. As in the previous case, we show how existing ideas for quantum computing with Alkali atoms such as entanglement via controlled collisions can be freed from important technical restrictions. We also provide additional details on the use of collisional losses from metastable states to perform gate operations via a lossy blockade mechanism.