Weakly measured while loops: peeking at quantum states

Pablo Andrés-Martínez, Chris Heunen

Research output: Contribution to journalArticlepeer-review

Abstract / Description of output

A while loop tests a termination condition on every iteration. On a quantum computer, such measurements perturb the evolution of the algorithm. We define a while loop primitive using weak measurements, offering a trade-off between the perturbation caused and the amount of information gained per iteration. This trade-off is adjusted with a parameter set by the programmer. We provide sufficient conditions that let us determine, with arbitrarily high probability, a worst-case estimate of the number of iterations the loop will run for. As an example, we solve Grover's search problem using a while loop and prove the quadratic quantum speed-up is maintained.
Original languageEnglish
Article number025007
Number of pages21
JournalQuantum Science and Technology
Issue number2
Publication statusPublished - 1 Apr 2022

Keywords / Materials (for Non-textual outputs)

  • programming primitive
  • weak measurement
  • while loop


Dive into the research topics of 'Weakly measured while loops: peeking at quantum states'. Together they form a unique fingerprint.

Cite this