Quantum Information Processing

, Volume 12, Issue 4, pp 1759–1779 | Cite as

Gaussian quantum computation with oracle-decision problems

  • Mark R. A. Adcock
  • Peter Høyer
  • Barry C. Sanders


We study a simple-harmonic-oscillator quantum computer solving oracle decision problems. We show that such computers can perform better by using nonorthogonal Gaussian wave functions rather than orthogonal top-hat wave functions as input to the information encoding process. Using the Deutsch–Jozsa problem as an example, we demonstrate that Gaussian modulation with optimized width parameter results in a lower error rate than for the top-hat encoding. We conclude that Gaussian modulation can allow for an improved trade-off between encoding, processing and measurement of the information.


Quantum algorithms Continuous-variable quantum computation Simple-harmonic oscillator quantum computer Oracle decision problems 


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Copyright information

© Springer Science+Business Media New York 2012

Authors and Affiliations

  • Mark R. A. Adcock
    • 1
  • Peter Høyer
    • 1
    • 2
  • Barry C. Sanders
    • 1
  1. 1.Institute for Quantum Information ScienceUniversity of CalgaryCalgaryCanada
  2. 2.Department of Computer ScienceUniversity of CalgaryCalgaryCanada

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