Experimentally obtaining maximal coherence via assisted distillation process

Assisted entanglement distillation

Motivated by the problem of designing quantum repeaters, we study entanglement distillation between two parties, Alice and Bob, starting from a mixed state and with the help of “repeater” stations. To treat the case of a single repeater, we extend the notion of entanglement of assistance to arbitrary mixed tripartite states and exhibit a protocol, based on a random coding strategy, for extracti...

On bound entanglement assisted distillation

We investigate asymptotic distillation of entanglement in the presence of an unlimited amount of bound entanglement for bi-partite systems. We show that the distillability is still bounded by the relative entropy of entanglement. This offers a strong support to the fact that bound entanglement does not improve distillation of entanglement. PACS number(s): 03.65.Bz, 89.70.+c,89.80.+h keywords: e...

Maximal privacy without coherence.

Privacy is a fundamental feature of quantum mechanics. A coherently transmitted quantum state is inherently private. Remarkably, coherent quantum communication is not a prerequisite for privacy: there are quantum channels that are too noisy to transmit any quantum information reliably that can nevertheless send private classical information. Here, we ask how much private classical information a...

Vacuum Booster for Distillation Process

Tight Bounds for Communication-Assisted Agreement Distillation

Suppose Alice holds a uniformly random string X ∈ {0, 1} and Bob holds a noisy version Y of X where each bit of X is flipped independently with probability ε ∈ [0, 2 ]. Alice and Bob would like to extract a common random string of min-entropy at least k. In this work, we establish the communication versus success probability trade-off for this problem by giving a protocol and a matching lower b...