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arXiv · 0808.4090

Reduced and projected two-particle entanglement at finite temperatures

P. Samuelsson·I. Neder·M. Buttiker
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Abstract

We present a theory for two-particle entanglement production and detection in mesoscopic conductors at finite temperature. In contrast to the zero temperature limit, the entanglement of the density matrix projected out of the emitted many-body state is different from the entanglement of the reduced density matrix, detectable by current correlation measurements. We show that under very general conditions the reduced entanglement constitutes a lower bound for the projected entanglement. Applying the theory to the recent experiment [Neder et al, Nature 448 333 (2007)] on a fermionic Hanbury Brown Twiss two-particle interferometer we find that despite an appreciable entanglement production in the experiment, the detectable entanglement is close to zero.

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P. Samuelsson, I. Neder, M. Buttiker. 2009-09-04. Reduced and projected two-particle entanglement at finite temperatures. https://doi.org/10.1103/physrevlett.102.106804

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