title: Experimental temporal quantum steering.
abstract: Temporal steering is a form of temporal correlation between the initial and final state of a quantum system. It is a temporal analogue of the famous Einstein-Podolsky-Rosen (spatial) steering. We demonstrate, by measuring the photon polarization, that temporal steering allows two parties to verify if they have been interacting with the same particle, even if they have no information about what happened with the particle in between the measurements. This is the first experimental study of temporal steering. We also performed experimental tests, based on the violation of temporal steering inequalities, of the security of two quantum key distribution protocols against individual attacks. Thus, these results can lead to applications for secure quantum communications and quantum engineering.
authors.affiliation: Faculty of Physics, Adam Mickiewicz University, PL-61-614 Poznań, Poland.|RCPTM, Joint Laboratory of Optics of Palacký University and Institute of Physics of the Czech Academy of Sciences, 17. listopadu 12, 772 07 Olomouc, Czech Republic.
authors.forename: Karol
authors.initials: K
authors.lastname: Bartkiewicz
authors.affiliation: Institute of Physics of the Czech Academy of Sciences, Joint Laboratory of Optics of Palacký University and Institute of Physics of the Czech Academy of Sciences, 17. listopadu 50A, 77207 Olomouc, Czech Republic.
authors.forename: Antonín
authors.initials: A
authors.lastname: Černoch
authors.affiliation: RCPTM, Joint Laboratory of Optics of Palacký University and Institute of Physics of the Czech Academy of Sciences, 17. listopadu 12, 772 07 Olomouc, Czech Republic.
authors.forename: Karel
authors.initials: K
authors.lastname: Lemr
authors.affiliation: Faculty of Physics, Adam Mickiewicz University, PL-61-614 Poznań, Poland.|CEMS, RIKEN, 351-0198 Wako-shi, Japan.
authors.forename: Adam
authors.initials: A
authors.lastname: Miranowicz
authors.affiliation: CEMS, RIKEN, 351-0198 Wako-shi, Japan.|Department of Physics, The University of Michigan, Ann Arbor, MI 48109-1040, USA.
authors.forename: Franco
authors.initials: F
authors.lastname: Nori