In this paper, we provide a class of bound entangled states that have positive distillable secure key rate. The smallest state of this kind is 4 circle times 4, which shows that peculiar security contained in bound entangled states does not need high-dimensional systems. We show that for these states a positive key rate can be obtained by one-way Devetak-Winter (DW) protocol. Subsequently, the volume of bound entangled key-distillable states for m circle times n Hilbert space with m, n >= 4 is shown to be nonzero. We provide a scheme of verification of cryptographic quality of experimentally prepared state in terms of local observables. Proposed set of seven collective settings is proven to be optimal in number of settings.
Authors
- Karol Horodecki,
- Łukasz Pankowski,
- Michał Horodecki,
- prof. dr hab. Paweł Horodecki link open in new tab
Additional information
- DOI
- Digital Object Identifier link open in new tab 10.1109/tit.2008.921709
- Category
- Publikacja w czasopiśmie
- Type
- artykuł w czasopiśmie z listy filadelfijskiej
- Language
- angielski
- Publication year
- 2008
