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Title: Two-qubit-entanglement in matter created by entangled-photon pairs: A perturbative analysis
We study entanglement created between two isolated qubits by interaction with entangled-photon pairs obtained by parametric down-conversion of a laser pump field. The induced entanglement is quantified using the mixed state Concurrence proposed by Wootters et al. [Phys. Rev. Lett. 78, 5022 (1997)]. A universal value of qubit-entanglement, which is independent on the photon-pair wavefunction is identified to leading order in the qubit–field interaction and the pump field amplitude. The qubit entanglement decreases at higher laser pump intensities due to interference between the entangled photon pairs, which creates excitations in the qubit system. Maximal Concurrence is produced by only generating coherences between the ground and the highest excited qubit states.  more » « less
Award ID(s):
2246379
PAR ID:
10614315
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
AVS Quantum Science
Date Published:
Journal Name:
AVS Quantum Science
Volume:
6
Issue:
3
ISSN:
2639-0213
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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