Interferometric distillation and determination of unknown two-qubit entanglement

Abstract

We propose a scheme for both distilling and quantifying entanglement, applicable to individual copies of an arbitrary unknown two-qubit state. It is realized in a usual two-qubit interferometry with local filtering. Proper filtering operation for the maximal distillation of the state is achieved, by erasing single-qubit interference, and then the concurrence of the state is determined directly from the visibilities of two-qubit interference. We compare the scheme with full state tomography.

References in corpus (1)

• On experimental procedures for entanglement verification

Cited by in corpus (3)

• Construction of optimal witness for unknown two-qubit entanglement
• Minimax optimization of entanglement witness operator for the quantification of three-qubit mixed-state entanglement
• Quantifying mixed-state quantum entanglement by optimal entanglement witness