Demonstration of a Quantum Switch in a Sagnac Configuration
- Author(s)
- Teodor Strömberg, Peter Schiansky, Robert W. Peterson, Marco Túlio Quintino, Philip Walther
- Abstract
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(s)
- Quantum Optics, Quantum Nanophysics and Quantum Information, Research Network Quantum Aspects of Space Time
- External organisation(s)
- Université Paris VI - Pierre-et-Marie-Curie, Österreichische Akademie der Wissenschaften (ÖAW), Universität Wien
- Journal
- Physical Review Letters
- Volume
- 131
- No. of pages
- 6
- ISSN
- 0031-9007
- DOI
- https://doi.org/10.48550/arXiv.2211.12540
- Publication date
- 08-2023
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103025 Quantum mechanics, 103026 Quantum optics
- ASJC Scopus subject areas
- Physics and Astronomy(all)
- Portal url
- https://ucris.univie.ac.at/portal/en/publications/demonstration-of-a-quantum-switch-in-a-sagnac-configuration(769dd923-527c-4aea-b629-bdbd385c8816).html