Oxford University Press eBooks

Atoms in a box

S. Haroche, J. M. Raimond

Published Aug 10, 2006• 0 citations

Abstract

This chapter describes the essential features of ion traps and the quantum information science that these systems make possible. Section 8.1 analyses the Paul trap design generally used in these experiments and describes how it operates with a single ion or with a set of ions making up a string of qubits. Section 8.2 focuses on the manipulation of the ion's motional states. Section 8.3 includes in the spin-spring model the ionic relaxation due to spontaneous emission, using the quantum jump language introduced in Chapter 4. Section 8.4 focuses on the scheme proposed by Cirac and Zoller that has been implemented in the laboratory on Ca+ ions by the Innsbruck group. The results of a teleportation experiment involving three ions are presented. In an alternative scheme, the Boulder group working on Be+ has realized gates in which the ions are addressed collectively. Section 8.5 shows how this has made it possible to prepare and analyse GHZ states with up to six ions. Section 8.6 concludes by discussing some of the perspectives opened by ion trap physics in quantum information science.

DOI: 10.1093/acprof:oso/9780198509141.003.0008

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