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Detecting N-particle interference patterns with linear balanced N-port analyzers

Ole Steuernagel
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Abstract

A standard two-path interferometer fed into a linear N-port analyzer with coincidence detection of its output ports is analyzed. The N-port is assumed to be implemented as a discrete Fourier transformation $\cal F$, i.e., to be balanced. For unbound bosons it allows us to detect N-particle interference patterns with an N-fold reduction of the observed de Broglie wavelength, perfect visibility and minimal noise. Because the scheme involves heavy filtering a lot of the signal is lost, yet, it is surprisingly robust against common experimental imperfections, and can be implemented with current technology.

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Ole Steuernagel. 2003-03-11. Detecting N-particle interference patterns with linear balanced N-port analyzers. https://arxiv.org/abs/quant-ph/0303068

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