title: Experimental observation of weak non-Markovianity.
abstract: Non-Markovianity has recently attracted large interest due to significant advances in its characterization and its exploitation for quantum information processing. However, up to now, only non-Markovian regimes featuring environment to system backflow of information (strong non-Markovianity) have been experimentally simulated. In this work, using an all-optical setup we simulate and observe the so-called weak non-Markovian dynamics. Through full process tomography, we experimentally demonstrate that the dynamics of a qubit can be non-Markovian despite an always increasing correlation between the system and its environment which, in our case, denotes no information backflow. We also show the transition from the weak to the strong regime by changing a single parameter in the environmental state, leading us to a better understanding of the fundamental features of non-Markovianity.
authors.affiliation: Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, Caixa Postal 702, 30161-970, Brazil.
authors.forename: Nadja K
authors.initials: NK
authors.lastname: Bernardes
authors.affiliation: Dipartimento di Fisica, Sapienza Università di Roma, Roma 00185, Italy.
authors.forename: Alvaro
authors.initials: A
authors.lastname: Cuevas
authors.affiliation: Dipartimento di Fisica, Sapienza Università di Roma, Roma 00185, Italy.|Télécom ParisTech, CNRS LTCI, 46 rue Barrault, F-75634 Paris Cedex 13, France.
authors.forename: Adeline
authors.initials: A
authors.lastname: Orieux
authors.affiliation: Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, Caixa Postal 702, 30161-970, Brazil.
authors.forename: C H
authors.initials: CH
authors.lastname: Monken
authors.affiliation: Dipartimento di Fisica, Sapienza Università di Roma, Roma 00185, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Mataloni
authors.affiliation: Dipartimento di Fisica, Sapienza Università di Roma, Roma 00185, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Sciarrino
authors.affiliation: Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, Caixa Postal 702, 30161-970, Brazil.
authors.forename: Marcelo F
authors.initials: MF
authors.lastname: Santos