title: Conditional cooling limit for a quantum channel going through an incoherent environment.
abstract: We propose and experimentally verify a cooling limit for a quantum channel going through an incoherent environment. The environment consists of a large number of independent non-interacting and non-interfering elementary quantum systems--qubits. The qubits travelling through the channel can only be randomly replaced by environmental qubits. We investigate a conditional cooling limit that exploits an additional probing output. The limit specifies when the single-qubit channel is quantum, i.e. it preserves entanglement. It is a fundamental condition for entanglement-based quantum technology.
authors.affiliation: Department of Optics, Faculty of Science, Palacký University, 17. listopadu 1192/12, 771 46 Olomouc, Czech Republic.
authors.forename: Ivo
authors.initials: I
authors.lastname: Straka
authors.affiliation: Department of Optics, Faculty of Science, Palacký University, 17. listopadu 1192/12, 771 46 Olomouc, Czech Republic.
authors.forename: Martina
authors.initials: M
authors.lastname: Miková
authors.affiliation: Department of Optics, Faculty of Science, Palacký University, 17. listopadu 1192/12, 771 46 Olomouc, Czech Republic.
authors.forename: Michal
authors.initials: M
authors.lastname: Mičuda
authors.affiliation: Department of Optics, Faculty of Science, Palacký University, 17. listopadu 1192/12, 771 46 Olomouc, Czech Republic.
authors.forename: Miloslav
authors.initials: M
authors.lastname: Dušek
authors.affiliation: Department of Optics, Faculty of Science, Palacký University, 17. listopadu 1192/12, 771 46 Olomouc, Czech Republic.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Ježek
authors.affiliation: Department of Optics, Faculty of Science, Palacký University, 17. listopadu 1192/12, 771 46 Olomouc, Czech Republic.
authors.forename: Radim
authors.initials: R
authors.lastname: Filip