W-like bound entangled states and secure key distillation

Abstract

We construct multipartite entangled states with underlying W-type structure satisfying positive partial transpose (PPT) condition under any (N-1)|1 partition. Then we show how to distill N-partite secure key form the states using two different methods: direct application of local filtering and novel random key distillation scheme in which we adopt the idea form recent results on entanglement distillation. Open problems and possible implications are also discussed.

Revtex, 7 pages, 3 figures, published version with updated references

References in corpus (7)

• Distillation of secret key and entanglement from quantum states
• Quantum Communication With Zero-Capacity Channels
• Relating quantum privacy and quantum coherence: an operational approach
• Thermal bound entanglement in macroscopic systems and area laws
• Physical Underpinnings of Privacy
• Random bipartite entanglement from W and W-like states
• Noisy Preprocessing and the Distillation of Private States