Abstract
We consider the problem of obtaining the entanglement witnesses for a given quantum system. We present a method to convert this problem to a standard convex optimization problem by defining a feasible region. Then we develop a generic two-step algorithm for this problem which can be applied to the entanglement detection of -partite quantum system. This permits an organized construction of nonlinear and linear entanglement witnesses for a given quantum system. To demonstrate the capability of this approach, we apply our results to several three-qubit systems which in some cases lead to necessary and sufficient conditions for separability.
- Received 1 June 2009
DOI:https://doi.org/10.1103/PhysRevA.80.052307
©2009 American Physical Society