Quantum entanglement in coupled lossy waveguides

Amit Rai, Sumanta Das, Girish Agarwal
2010 Optics Express  
We investigate the viability of coupled waveguides as basic units of quantum circuits. We study entanglement when the waveguides are fed in by light produced by a down-converter working either in low gain limit or under large gain. We present explicit analytical results for the measure of entanglement in terms of the logarithmic negativity for a variety of input states. We also address the effect of loss on entanglement dynamics of waveguide modes. Our results indicate that the waveguide
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doi:10.1364/oe.18.006241 pmid:20389647 fatcat:hg5uiqsuojgahblnwxibi7z3gq