Picture of smart phone in human hand

World leading smartphone and mobile technology research at Strathclyde...

The Strathprints institutional repository is a digital archive of University of Strathclyde's Open Access research outputs. Strathprints provides access to thousands of Open Access research papers by University of Strathclyde researchers, including by Strathclyde researchers from the Department of Computer & Information Sciences involved in researching exciting new applications for mobile and smartphone technology. But the transformative application of mobile technologies is also the focus of research within disciplines as diverse as Electronic & Electrical Engineering, Marketing, Human Resource Management and Biomedical Enginering, among others.

Explore Strathclyde's Open Access research on smartphone technology now...

Comparison of two unknown pure quantum states

Barnett, Stephen M. and Chefles, Anthony and Jex, Igor (2003) Comparison of two unknown pure quantum states. Physics Letters A, 307 (4). pp. 189-195. ISSN 0375-9601

[img]
Preview
Text (strathprints005857)
strathprints005857.pdf - Accepted Author Manuscript

Download (112kB) | Preview

Abstract

Can we establish whether or not two quantum systems have been prepared in the same state? We investigate the possibility of universal unambiguous state comparison. We show that it is impossible to conclusively identify two pure unknown states as being identical, and construct the optimal measurement for conclusively identifying them as being different. We then derive optimal strategies for state comparison when the state of each system is one of two known states.