Details

Autor(en) / Beteiligte

• Nha, Hyunchul
• Kim, Jaewan

Titel

Entanglement criteria via the uncertainty relations in su(2) and su(1,1) algebras: Detection of non-Gaussian entangled states

Ist Teil von

• Physical review. A, Atomic, molecular, and optical physics, 2006-07, Vol.74 (1), Article 012317

Ort / Verlag

United States

Erscheinungsjahr

2006

Quelle

American Physical Society

Beschreibungen/Notizen

• We derive a class of inequalities, from the uncertainty relations of the su(1,1) and the su(2) algebra in conjunction with partial transposition, that must be satisfied by any separable two-mode states. These inequalities are presented in terms of the su(2) operators J{sub x}=(a{sup {dagger}}b+ab{sup {dagger}})/2, J{sub y}=(a{sup {dagger}}b-ab{sup {dagger}})/2i, and the total photon number <N{sub a}+N{sub b}>. They include as special cases the inequality derived by Hillery and Zubairy [Phys. Rev. Lett. 96, 050503 (2006)], and the one by Agarwal and Biswas [New J. Phys. 7, 211 (2005)]. In particular, optimization over the whole inequalities leads to the criterion obtained by Agarwal and Biswas. We show that this optimal criterion can detect entanglement for a broad class of non-Gaussian entangled states, i.e., the su(2) minimum-uncertainty states. Experimental schemes to test the optimal criterion are also discussed, especially the one using linear optical devices and photodetectors.