Demonstration of a Quantum Switch in a Sagnac Configuration

Autor(en)

Teodor Strömberg, Peter Schiansky, Robert W. Peterson, Marco Túlio Quintino, Philip Walther

Abstrakt

The quantum switch is an example of a process with an indefinite causal structure, and has attracted attention for its ability to outperform causally ordered computations within the quantum circuit model. To date, realizations of the quantum switch have made a trade-off between relying on optical interferometers susceptible to minute path length fluctuations and limitations on the range and fidelity of the implementable channels, thereby complicating their design, limiting their performance, and posing an obstacle to extending the quantum switch to multiple parties. In this Letter, we overcome these limitations by demonstrating an intrinsically stable quantum switch utilizing a common-path geometry facilitated by a novel reciprocal and universal SU(2) polarization gadget. We certify our design by successfully performing a channel discrimination task with near unity success probability.

Organisation(en)

Quantenoptik, Quantennanophysik und Quanteninformation, Forschungsverbund Quantum Aspects of Space Time

Externe Organisation(en)

Université Paris VI - Pierre-et-Marie-Curie, Österreichische Akademie der Wissenschaften (ÖAW), Universität Wien

Journal

Physical Review Letters

Band

131

Anzahl der Seiten

6

ISSN

0031-9007

DOI

https://doi.org/10.48550/arXiv.2211.12540

Publikationsdatum

08-2023

Peer-reviewed

Ja

ÖFOS 2012

103025 Quantenmechanik, 103026 Quantenoptik

ASJC Scopus Sachgebiete

Allgemeine Physik und Astronomie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/769dd923-527c-4aea-b629-bdbd385c8816