25 papers · ranked by Valyu relevance
Mattia Walschaers
Gaussian states have played on important role in the physics of continuous-variable quantum systems. They are appealing for the experimental ease with which they can be produced, and for their compact and elegant mathematical description. Nevertheless, many proposed quantum technologies require us to go beyond the…
Carlos Navarrete–Benlloch
A particularly important class of quantum mechanical states of the harmonic oscillator are the so-called Gaussian states, that is, states which have a Gaussian Wigner function; as we will see, these are the type of light states which are naturally generated in the laboratory, although we will also show how to design…
Yangyang Wang, Xiaofei Qi, Jinchuan Hou
A measure of nonclassicality $N$ in terms of local Gaussian unitary operations for bipartite Gaussian states is introduced. $N$ is a faithful quantum correlation measure for Gaussian states as product states have no such correlation and every non product Gaussian state contains it. For any bipartite Gaussian state…
Jorge R. Bolaños-Servín, Roberto Quezada, Josué I. Rios-Cangas
We give a rigorous definition of moments of an unbounded observable with respect to a quantum state in terms of Yosida's approximations of unbounded generators of contractions semigroups. We use this notion to characterize Gaussian states in terms of annihilation moments. As a by-product, rigorous formulae for the mean…
Motohisa Fukuda, Robert Koenig
We consider ensembles of bipartite states resulting from a random passive Gaussian unitary applied to a fiducial pure Gaussian state. We show that the symplectic spectra of the reduced density operators concentrate around that of a thermal state with the same energy. This implies, in particular, concentration of the…
Angelo Carollo, Bernardo Spagnolo, Davide Valenti
In this article, we derive a closed form expression for the symmetric logarithmic derivative of Fermionic Gaussian states. This provides a direct way of computing the quantum Fisher Information for Fermionic Gaussian states. Applications range from quantum Metrology with thermal states to non-equilibrium steady states…
Julio A. López-Saldívar, Margarita A. Man’ko, Vladimir I. Man’ko
In the differential approach elaborated, we study the evolution of the parameters of Gaussian, mixed, continuous variable density matrices, whose dynamics are given by Hermitian Hamiltonians expressed as quadratic forms of the position and momentum operators or quadrature components. Specifically, we obtain in generic…
Bohan Li, Aritra Das, Spyros Tserkis, Prineha Narang + 2 more
'Syed M. Assad'] The maximum amount of entanglement achievable under passive transformations by continuous-variable states is called the entanglement potential. Recent work has demonstrated that the entanglement potential is upper-bounded by a simple function of the squeezing of formation, and that certain classes of…
Liang Liu, Jinchuan Hou, Xiaofei Qi, Aurelian Isar
Generally speaking, it is difficult to compute the values of the Gaussian quantum discord and Gaussian geometric discord for Gaussian states, which limits their application. In the present paper, for any $((n+m))$-mode continuous-variable system, a computable Gaussian quantum correlation $M$ is proposed. For any state…
Yuan Yao, Filippo M. Miatto, Nicolás Quesada
We propose a framework to design and optimize generic photonic quantum circuits composed of Gaussian objects (pure and mixed Gaussian states, Gaussian unitaries, Gaussian channels, Gaussian measurements) as well as non-Gaussian effects such as photon-number-resolving measurements. In this framework, we parametrize a…
Julio A. López-Saldívar, Margarita A. Man’ko, V. I. Man’ko
In a differential approach elaborated, we study the evolution of the parameters of Gaussian, mixed, continuous variable density matrices, whose dynamics are given by Hermitian Hamiltonians expressed as quadratic forms of the position and momentum operators or quadrature components. Specifically, we obtain in generic…
Maurice de Gosson, Charlyne de Gosson
We use the notion of polar duality from convex geometry and the theory of Lagrangian planes from symplectic geometry to construct a fiber bundle over ellipsoids that can be viewed as a quantum-mechanical substitute for the classical symplectic phase space. The total space of this fiber bundle consists of geometric…
Roman Schnabel
The amazing quantum effect of ‘entanglement’ was discovered in the 1935 thought experiment by Albert Einstein, Boris Podolsky and Nathan Rosen (‘EPR’)1. The ensuing research opened up fundamental questions and led to experiments that proved that quantum theory cannot be completed by local hidden variables2-4.…
Ismail El Korde, Jason M. Lewis, Erik Clarkson, Tommy Dam + 3 more
Single-particle tracking methods have emerged as a crucial tool for the characterization of dynamical and diffusive processes in a range of biological and synthetic systems. Here, we propose a simple and light-weight yet accurate method for the segmentation of multi-state Brownian trajectories based on an optimised…
Mingjian He, Proloy Das, Gladia Hotan, Patrick L. Purdon
Linear parametric state-space models are a ubiquitous tool for analyzing neural time series data, providing a way to characterize the underlying brain dynamics with much greater statistical efficiency than non-parametric data analysis approaches. However, neural time series data are frequently time-varying, exhibiting…
Ismail El Korde, Jason M. Lewis, Erik Clarkson, Tommy Dam + 3 more
Single-particle tracking methods have emerged as a crucial tool for the characterization of dynamical and diffusive processes in a range of biological and synthetic systems. Here, we propose a simple and light-weight yet accurate method for the segmentation of multi-state Brownian trajectories based on an optimised…
Authors not listed
Molecular Polariton is becoming one of the leading directions to control a multitude of chemical and physical processes, such as charge transfer, selective bond breaking, and excited state dynamics. Accurately and efficiently simulating polariton properties under the collective coupling regimes (between $N$ molecules…
Authors not listed
Nonadiabatic effects arising from conical intersections between excited states play a crucial role in the optical properties of a wide range of chromophores and have to be accounted for in first-principles modeling of spectral lineshapes. In this work, we investigate the importance of nonadiabatic effects in the…
R. M. Razban, E. I. Shakhnovich
The distribution of protein stability effects is known to be well-approximated by a Gaussian distribution from previous empirical fits. Starting from first-principles statistical mechanics, we more rigorously motivate this empirical observation by deriving per residue protein stability effects to be Gaussian. Our…
M. Nicolás Cruz-Bournazou, Harini Narayanan, Alessandro Fagnani, Alessandro Butté
Hybrid modeling, meaning the integration of data-driven and knowledge-based methods, is quickly gaining popularity among many research fields, including bioprocess engineering and development. Recently, the data-driven part of hybrid methods have been largely extended with machine learning algorithms (e.g., artificial…
Beliz Sertcan, Jürg Hutter, Anna-Sophia Hehn
Augmented plane wave methods enable an efficient description of atom-centered or localized features of the electronic density, circumventing high energy cutoffs and thus prohibitive computational costs of pure plane wave formulations. To complement existing implementations for ground-state properties and excitation…
Amelia Carolina Sparavigna
Previous studies (Sparavigna, 2023) have demonstrated the Tsallis q-Gaussian functions suitable for the analysis of Raman spectra. Here we consider two asymmetric forms of them, with the aim of further improving the fitting of Raman spectra. The first asymmetric form, that we are here proposing for the first time, is a…
Benjamin X. K. Chng, Wenxiang Ying, Yifan Lai, A. Nickolas Vamivakas + 3 more
Molecular polaritons, the hybridization of electronic states in molecules with photonic excitation inside a cavity, play an important role in fundamental quantum science and technology. Understanding the de-coherence mechanism of molecular polaritons is among the most significant fundamental questions. We theoretically…
Amelia Carolina Sparavigna
In an article by Thibault et al., 2002, we can find measurements of Raman linewidths in the Q branch of carbon monoxide, for mixtures with Argon at different temperatures. A plot is available for the Q(5) line with a fitted Voigt function. Here we show that a q-Gaussian Tsallis function can be used for fitting this…
Arkajit Mandal, Michael Taylor, Braden Weight, Eric Koessler + 2 more
When molecules are coupled to an optical cavity, new light-matter hybrid states, so-called polaritons, are formed due to quantum light-matter interactions. With the experimental demonstrations of modifying chemical reactivities by forming polaritons under strong light-matter interactions, theorists have been encouraged…