# Accession Number:

## AD1028242

# Title:

## Genuinely Multipartite Concurrence of N-qubit X Matrices (Author's Final Manuscript)

# Descriptive Note:

## Journal Article

# Corporate Author:

## ROCHESTER UNIV NY ROCHESTER United States

# Personal Author(s):

# Report Date:

## 2012-12-05

# Pagination or Media Count:

## 8.0

# Abstract:

We find an algebraic formula for the N-partite concurrence of N qubits in an X-matrix. X-matrices are density matrices whose only non-zero elements are diagonal or anti-diagonal when written in an orthonormal basis. We use our formula to study the dynamics of the N-partite entanglement of N remote qubits in generalized N-party Greenberger-Horne-Zeilinger GHZ states. We study the case when each qubit interacts with a local amplitude damping channel. It is shown that only one type of GHZ state loses its entanglement in finite time for the rest, N-partite entanglement dies out asymptotically. Algebraic formulas for the entanglement dynamics are given in both cases. We directly confirm that the half-life of the entanglement is proportional to the inverse of N. When entanglement vanishes in finite time, the time at which entanglement vanishes can decrease or increase with N depending on the initial state. In the macroscopic limit, this time is independent of the initial entanglement.

# Descriptors:

# Subject Categories:

- Quantum Theory and Relativity