We consider Gaussian quantum circuits supplemented with non-Gaussian input states and derive sufficient conditions for efficient classical strong simulation of these circuits. In particular, we generalise the stellar representation continuous-variable to multimode setting relate rank states, a recently introduced measure non-Gaussianity, cost evaluating classically output probability densities ...

This article presents a new image denoising algorithm that uses Gaussian Symmetric Markov random fields based on maximum posteriori estimation. First, an model is built, and the problem was converted to estimation problem. The prior probability of can be estimated using Gibbs distribution, which equivalent fields. Second, calculated expectation-maximization conjugate gradient method, where used...

In this paper, the nonlinear lattice-Hammerstein filter and its properties are derived. It is shown that the error signals are orthogonal to the input signal and also backward errors of different stages are orthogonal to each other. Numerical results confirm all the theoretical properties of the lattice-Hammerstein structure.

We establish fundamental upper bounds on the amount of secret key that can be extracted from quantum Gaussian states by using local operations, classical processing, and public communication. For one-way communication or when two-way is allowed but Alice Bob first perform destructive measurements, we prove bounded R\'enyi-2 entanglement formation ${E}_{F,2}^{\mathrm{G}}$. The saturation this in...