Applied Physics B

, 124:90 | Cite as

Intensity stabilisation of optical pulse sequences for coherent control of laser-driven qubits

  • Joseph Thom
  • Ben Yuen
  • Guido Wilpers
  • Erling Riis
  • Alastair G. Sinclair


We demonstrate a system for intensity stabilisation of optical pulse sequences used in laser-driven quantum control of trapped ions. Intensity instability is minimised by active stabilisation of the power (over a dynamic range of \(> 10^{4}\)) and position of the focused beam at the ion. The fractional Allan deviations in power were found to be \(<2.2 \times 10^{-4}\) for averaging times from 1 to 16,384 s. Over similar times, the absolute Allan deviation of the beam position is \(<0.1\) \(\upmu\)m for a 45 \({\upmu }\)m beam diameter. Using these residual power and position instabilities, we estimate the associated contributions to infidelity in example qubit logic gates to be below \(10^{-6}\) per gate.



We thank E. Theocharous (NPL) for assistance in detector characterisation. We thank the following individuals for informative discussions: D. Szwer (NPL), D. Lucas and C. Ballance (Oxford), and C. Roos (Innsbruck). This work was funded by the UK National Measurement Office and project EXL01 QESOCAS of the European Metrology Research Programme (EMRP) [Grant Agreement No. 912/2009/EC]. The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union. JT was supported by the EPSRC Industrial Doctorate Centre in Optics and Photonics. BY was supported by an EPSRC Knowledge Transfer Secondment from Imperial College London.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.National Physical LaboratoryTeddingtonUK
  2. 2.Department of PhysicsUniversity of StrathclydeGlasgowUK
  3. 3.Department of PhysicsImperial CollegeLondonUK
  4. 4.M Squared LasersGlasgowUK
  5. 5.Department of PhysicsUniversity of Oxford, Clarendon LaboratoryOxfordUK

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