A. Chia, T. Paterek, and L. C. Kwek,

Quantum 1, 19 (2017). https://doi.org/10.22331/q-2017-07-21-19

We define the hitting time for a model of continuous-time open quantum walks in terms of quantum jumps. Our starting point is a master equation in Lindblad form, which can be taken as the qu…

Yoshifumi Nakata, Christoph Hirche, Ciara Morgan, and Andreas Winter,

Quantum 1, 18 (2017). https://doi.org/10.22331/q-2017-07-21-18

We investigate decoupling, one of the most important primitives in quantum Shannon theory, by replacing the uniformly distributed random unitaries commonly used to achieve the protocol, with…

Manuel Gessner, Luca Pezzè, and Augusto Smerzi,

Quantum 1, 17 (2017). https://doi.org/10.22331/q-2017-07-14-17

We introduce a multi-mode squeezing coefficient to characterize entanglement in $N$-partite continuous-variable systems. The coefficient relates to the squeezing of collective observables in…

Thomas D. Galley and Lluis Masanes,

Quantum 1, 15 (2017). https://doi.org/10.22331/q-2017-07-14-15

The standard postulates of quantum theory can be divided into two groups: the first one characterizes the structure and dynamics of pure states, while the second one specifies the structure…

Marco Tomamichel and Anthony Leverrier,

Quantum 1, 14 (2017). https://doi.org/10.22331/q-2017-07-14-14

In this work we present a security analysis for quantum key distribution, establishing a rigorous tradeoff between various protocol and security parameters for a class of entanglement-based…

John-Mark A. Allen, Owen J. E. Maroney, and Stefano Gogioso,

Quantum 1, 13 (2017). https://doi.org/10.22331/q-2017-07-14-13

Macro-realism is the position that certain macroscopic observables must always possess definite values: e.g. the table is in some definite position, even if we do not know what that is preci…