[quantum-info] PIQuDos seminar Wed March 4: Nengkun Yu

[Gus Gutoski]

Reminder: Nengkun Yu on Wed Mar 4 at 4pm in the Time room.

On Fri, Feb 27, 2015 at 1:19 PM, Gus Gutoski
<ggutoski at perimeterinstitute.ca> wrote:
> Please join us on Wednesday, March 4 at 4pm in the Time room for a
> quantum information seminar by Nengkun Yu.
>
> Separability of Bosonic Systems
>
> We study the separability of quantum states in bosonic system. Our
> main tool here is the "separability witnesses", and a connection
> between "separability witnesses" and a new kind of positivity of
> matrices--- "Power Positive Matrices" is drawn. Such connection is
> employed to demonstrate that multi-qubit quantum states with Dicke
> states being its eigenvectors is separable if and only if two related
> Hankel matrices are positive semidefinite. By employing this
> criterion, we are able to show that such state is separable if and
> only if it's partial transpose is non-negative, which confirms the
> conjecture in [Wolfe, Yelin, Phys. Rev. Lett. (2014)]. Then, we
> present a class of bosonic states in d⊗d system such that for general
> d, determine its separabilityNP-hard although verifiable conditions
> for separability is easily derived in case d=3,4.