Applied Physics B

, Volume 79, Issue 8, pp 979–986 | Cite as

Towards a scalable quantum computer/simulator based on trapped ions

  • T. SchaetzEmail author
  • D. Leibfried
  • J. Chiaverini
  • M.D. Barrett
  • J. Britton
  • B. DeMarco
  • W.M. Itano
  • J.D. Jost
  • C. Langer
  • D.J. Wineland


We describe the concept and experimental demonstration of the basic building blocks of a scalable quantum computer using trapped-ion qubits. The trap structure is divided into subregions where ion qubits can either be held as memory or subjected to individual rotations and multi-qubit gates in processor zones. Thus, ion qubits can become entangled in one trapping zone, then separated and distributed to separate zones (by switching control-electrode potentials) where subsequent single- and two-ion gates, and/or detection is performed. Recent work using these building blocks includes (1) demonstration of a dense-coding protocol, (2) demonstration of enhanced qubit-detection efficiency using quantum logic, (3) generation of GHZ states and their application to enhanced precision in spectroscopy, and (4) the realization of teleportation with atomic qubits. In the final section an analog quantum computer that could provide a shortcut towards quantum simulations under requirements less demanding than those for a universal quantum computer is also described.


Scalable Quantum Gate Operation Quantum Simulation Bell Measurement Raman Beam 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  • T. Schaetz
    • 1
    Email author
  • D. Leibfried
    • 1
  • J. Chiaverini
    • 1
  • M.D. Barrett
    • 1
  • J. Britton
    • 1
  • B. DeMarco
    • 1
  • W.M. Itano
    • 1
  • J.D. Jost
    • 1
  • C. Langer
    • 1
  • D.J. Wineland
    • 1
  1. 1.National Institute of Standards and TechnologyBoulderUSA

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