Fast and robust quantum computation with ionic Wigner crystals

TitleFast and robust quantum computation with ionic Wigner crystals
Publication TypeJournal Article
Year of Publication2011
AuthorsBaltrusch, JD, Negretti, A, Taylor, JM, Calarco, T
JournalPhysical Review A
Date Published2011/4/15

We present a detailed analysis of the modulated-carrier quantum phase gate implemented with Wigner crystals of ions confined in Penning traps. We elaborate on a recent scheme, proposed by two of the authors, to engineer two-body interactions between ions in such crystals. We analyze for the first time the situation in which the cyclotron (w_c) and the crystal rotation (w_r) frequencies do not fulfill the condition w_c=2w_r. It is shown that even in the presence of the magnetic field in the rotating frame the many-body (classical) Hamiltonian describing small oscillations from the ion equilibrium positions can be recast in canonical form. As a consequence, we are able to demonstrate that fast and robust two-qubit gates are achievable within the current experimental limitations. Moreover, we describe a realization of the state-dependent sign-changing dipole forces needed to realize the investigated quantum computing scheme.

Short TitlePhys. Rev. A