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Related papers: Recovery Map for Fermionic Gaussian Channels

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Decoherence of quantum systems is described by quantum channels. However, a complete understanding of such channels, especially in the multi-particle setting, is still an ongoing difficult task. We propose the family of quantum maps that…

We study the possibility of performing quantum state reconstruction from a measurement record that is obtained as a sequence of expectation values of a Hermitian operator evolving under repeated application of a single random unitary map,…

Quantum Physics · Physics 2010-04-29 Seth T. Merkel , Carlos A. Riofrio , Steven T. Flammia , Ivan H. Deutsch

Fermionic Gaussian unitaries are known to be efficiently learnable and simulatable. In this paper, we present a learning algorithm that learns an $n$-mode circuit containing $t$ parity-preserving non-Gaussian gates. While circuits with $t =…

Quantum Physics · Physics 2025-04-23 Sharoon Austin , Mauro E. S. Morales , Alexey Gorshkov

We investigate work extraction from non-interacting fermions under arbitrary unitary operations and the more restricted class of Gaussian unitary operations that can be feasibly implemented. We characterize general quantum states in…

Quantum Physics · Physics 2018-10-17 Marvellous Onuma-Kalu , Robert B. Mann

Using the known possibility to associate the completely positive maps with density matrices and recent results on expressing the density matrices with sets of classical probability distributions of dichotomic random variables we construct…

Quantum Physics · Physics 2019-04-09 Ashot Avanesov , Vladimir I. Man'ko

This document is meant to be a practical introduction to the analytical and numerical manipulation of Fermionic Gaussian systems. Starting from the basics, we move to relevant modern results and techniques, presenting numerical examples and…

Quantum Physics · Physics 2022-05-18 Jacopo Surace , Luca Tagliacozzo

We prove the existence of a universal recovery channel that approximately recovers states on a v. Neumann subalgebra when the change in relative entropy, with respect to a fixed reference state, is small. Our result is a generalization of…

Quantum Physics · Physics 2020-06-16 Thomas Faulkner , Stefan Hollands , Brian Swingle , Yixu Wang

The simulation of entangled ground-states of quantum materials remains challenging for classical computational methods in more than one spatial dimension, and is a prime target for quantum computational advantage. To this end, an important…

Quantum Physics · Physics 2025-06-05 Sing Lam Wong , Andrew C. Potter

It has been proposed that random wide neural networks near Gaussian process are quantum field theories around Gaussian fixed points. In this paper, we provide a novel map with which a wide class of quantum mechanical systems can be cast…

High Energy Physics - Theory · Physics 2024-03-19 Koji Hashimoto , Yuji Hirono , Jun Maeda , Jojiro Totsuka-Yoshinaka

We consider discrete time feedback aimed at reclaiming quantum information after a channel action. We compare Bayesian and Markovian strategies. We show that the former does not offer any advantage for qubit channels, while its superior…

Quantum Physics · Physics 2024-07-23 Milajiguli Rexiti , Samad Khabbazi Oskouei , Stefano Mancini

We consider a model of bosonic memory channel, which induces correlations among the transmitted signals. The application of suitable unitary transformations at encoding and decoding stages allows the complete removal of correlations,…

Quantum Physics · Physics 2012-02-01 Cosmo Lupo , Laleh Memarzadeh , Stefano Mancini

Gaussian filters have applications in a variety of areas in computer science, from computer vision to speech recognition. The collapsing sum is a matrix operator that was recently introduced to study Gaussian filters combinatorially. In…

Combinatorics · Mathematics 2021-12-30 Travis Dillon

We prove that a classical computer can efficiently sample from the photon-number probability distribution of a Gaussian state prepared by using an optical circuit that is shallow and local. Our work generalizes previous known results for…

Bosonic qubits are a promising route to building fault-tolerant quantum computers on a variety of physical platforms. Studying the performance of bosonic qubits under realistic gates and measurements is challenging with existing analytical…

Gaussian states, operations, and measurements are central building blocks for continuous-variable quantum information processing which paves the way for abundant applications, especially including network-based quantum computation and…

Quantum Physics · Physics 2021-07-06 Mengzhen Zhang

The entanglement negativity is a versatile measure of entanglement that has numerous applications in quantum information and in condensed matter theory. It can not only efficiently be computed in the Hilbert space dimension, but for…

Quantum Physics · Physics 2018-04-25 J. Eisert , V. Eisler , Z. Zimborás

Memory effects in open quantum dynamics are often incorporated in the equation of motion through a superoperator known as the memory kernel, which encodes how past states affect future dynamics. However, the usual prescription for…

Quantum Physics · Physics 2018-07-13 Felix A. Pollock , Kavan Modi

We present two projects concerning the main part of my PhD work. In the first one we study quantum channels, which are the most general operations mapping quantum states into quantum states, from the point of view of their divisibility…

Quantum Physics · Physics 2020-09-02 David Davalos

We present a novel Kalman filter for spatiotemporal systems called the numerical Gaussian process Kalman filter (GPKF). Numerical Gaussian processes have recently been introduced as a physics informed machine learning method for simulating…

Systems and Control · Electrical Eng. & Systems 2021-05-06 Armin Küper , Steffen Waldherr

Using the quantum map formalism, we provide a framework to construct fuzzy and coarse grained quantum states of many-body systems that account for limitations in the resolution of real measurement devices probing them. The first set of maps…

Quantum Physics · Physics 2021-11-02 Carlos Pineda , David Davalos , Carlos Viviescas , Antonio Rosado