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arXiv · quant-ph/9604020

Multi-mode density matrices of light via amplitude and phase control

T. Opatrny·D. -G. Welsch·W. Vogel
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Abstract

A new method is described for determining the quantum state of correlated multimode radiation by interfering the modes and measuring the statistics of the superimposed fields in four-port balanced homodyne detection. The full information on the $N$-mode quantum state is obtained by controlling both the relative amplitudes and the phases of the modes, which simplifies the reconstruction of density matrices to only $N+1$ Fourier transforms. In particular, this method yields time-correlated multimode density matrices of optical pulses by superimposing the signal by a sequence of short local-oscillator pulses.

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T. Opatrny, D. -G. Welsch, W. Vogel. 1996-04-22. Multi-mode density matrices of light via amplitude and phase control. https://doi.org/10.1016/s0030-4018(96)00548-2

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