A1 Journal article – refereed
Beating the limits with initial correlations

List of Authors: Daniel Basilewitsch, Rebecca Schmidt, Dominique Sugny, Sabrina Maniscalco, Christiane P. Koch
Publisher: Institute of Physics Publishing
Publication year: 2017
Journal: New Journal of Physics
Journal name in source: New Journal of Physics
Volume number: 19
Issue number: 11
Number of pages: 16
ISSN: 1367-2630


Fast and reliable reset of a qubit is a key prerequisite for any quantum technology. For real world open
quantum systems undergoing non-Markovian dynamics, reset implies not only purification, but in
particular erasure of initial correlations between qubit and environment. Here, we derive optimal reset
protocols using a combination of geometric and numerical control theory. For factorizing initial
states, we find a lower limit for the entropy reduction of the qubit as well as a speed limit. The timeoptimal
solution is determined by the maximum coupling strength. Initial correlations, remarkably,
allow for faster reset and smaller errors. Entanglement is not necessary.

Downloadable publication

This is an electronic reprint of the original article.
This reprint may differ from the original in pagination and typographic detail. Please cite the original version.

Last updated on 2019-16-07 at 18:09