Two independent photon pairs versus four-photon entangled states in parametric down conversion
Two independent photon pairs versus four-photon entangled states in parametric down conversion
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DOI：
10.1080/09500340408232478
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发表时间：
2003-10
影响因子：
1.3
通讯作者：
H. Riedmatten;V. Scarani;I. Marcikic;A. Acín;W. Tittel;H. Zbinden;N. Gisin
中科院分区：
文献类型：
--
作者：
H. Riedmatten;V. Scarani;I. Marcikic;A. Acín;W. Tittel;H. Zbinden;N. Gisin
Abstract We study the physics of four-photon states generated in spontaneous parametric down-conversion with a pulsed pump field. In the limit where the coherence time of the photons t ph c is much shorter than the duration of the pump pulse Δt, the four photons can be described as two independent pairs. In the opposite limit, the four photons are in a four-particle entangled state. Any intermediate case can be characterized by a single parameter χ, which is a function of t ph c Δt. We present a direct measurement of χ through a simple experimental set-up. The full theoretical analysis is also provided.
