An Introduction to Trapped Ions, Scalability and Quantum Metrology

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Part of the Scottish Graduate Series book series (SGS)

Abstract

This article presents an introductory overview of three separate experimental aspects of ion trapping. It begins by discussing the various conventional approaches to confining charged particles, along with standard experimental techniques for laser cooling, coherent spectroscopy and quantum state preparation. Ion heating, a potential obstacle to experiments in quantum coherence is also discussed. For trapped ions to continue to advance in the field of quantum information, scalable trapping arrays are considered an essential technological component. Examples of the various approaches which have been pursued are outlined. A specific case study of a microtrap developed at NPL is presented, to exemplify the considerations needed in creating an operational device. A significant application of trapped ions is in quantum metrology, and more specifically in optical atomic clocks. The operational principle of a single-ion clock is described, and candidate species are highlighted. Advanced techniques for quantum state preparation and readout can now be used to enable frequency comparisons with unprecedented precision. This suggests that trapped ions will offer new levels of measurement sensitivity, the impact of which could range across optical atomic clocks, fundamental physics and navigation.

Keywords

Optical Clock Clock Transition Motional Frequency Quantum Metrology Doppler Cool 
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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Notes

Acknowledgments

This research at NPL which is cited in this article was supported by NPLs strategic research programme, the Pathfinder Metrology Programme of the UK National Measurement Office, the EU STREP project MICROTRAP, and the EU network SCALA. The author thanks G. Wilpers for critical reading of the manuscript.

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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  1. 1.National Physical LaboratoryMiddlesexTeddingtonUK

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