English
Related papers

Related papers: Quantum Feedback Networks: Hamiltonian Formulation

200 papers

Network tomography refers to the use of inference techniques for inferring internal network states from end-to-end probes. Quantum probes, implemented by sending blocks of $n$ coherent-state pulses augmented with continuous-variable (CV)…

Quantum Physics · Physics 2026-04-29 Yufei Zheng , Zihao Gong , Saikat Guha , Don Towsley

Identifying an accurate model for the dynamics of a quantum system is a vexing problem that underlies a range of problems in experimental physics and quantum information theory. Recently, a method called quantum Hamiltonian learning has…

Quantum Physics · Physics 2014-04-23 Nathan Wiebe , Christopher Granade , Christopher Ferrie , David G. Cory

The purpose of this paper is to present simple and general algebraic methods for describing series connections in quantum networks. These methods build on and generalize existing methods for series (or cascade) connections by allowing for…

Quantum Physics · Physics 2009-04-09 J. Gough , M. R. James

Networks of globally coupled, noise activated, bistable elements with connection time delays are considered. The dynamics of these systems is studied numerically using a Langevin description and analytically using (1) a Gaussian…

Statistical Mechanics · Physics 2009-11-11 Daniel Huber , Lev Tsimring

As the inevitable development trend of quantum key distribution, quantum networks have attracted extensive attention, and many prototypes have been deployed over recent years. Existing quantum networks based on optical fibers or quantum…

Quantum Physics · Physics 2019-04-29 Dong Jiang , Weicong Huang , Chaohui Gao , Jia Liu , Lijun Chen

Attention-based neural networks such as transformers have revolutionized various fields such as natural language processing, genomics, and vision. Here, we demonstrate the use of transformers for quantum feedback control through both a…

Quantum Physics · Physics 2026-02-26 Pranav Vaidhyanathan , Florian Marquardt , Mark T. Mitchison , Natalia Ares

We consider the CNOT quantum gate as a physical action, i.e. as unitary in time evolution of the two-qubit system. This points to the modeling of the interaction Hamiltonian of the two-qubit system which would correspond to the CNOT…

Quantum Physics · Physics 2007-05-23 Miroljub Dugic

In recent quantum algorithmic developments, a feedback-based approach has shown promise for preparing quantum many-body system ground states and solving combinatorial optimization problems. This method utilizes quantum Lyapunov control to…

This work presents an exactly soluble scheme to address the problem of optimal transfer of quantum states through a set of $s$ harmonic oscillators composing a network with connected ends as a closed quantum circuit. For this purpose we…

Quantum Physics · Physics 2014-07-18 Dirceu Portes , Hilario Rodrigues , Sergio B. Duarte , Basilio Baseia

A genuine feature of projective quantum measurements is that they inevitably alter the mean energy of the observed system if the measured quantity does not commute with the Hamiltonian. Compared to the classical case, Jacobs proved that…

Statistical Mechanics · Physics 2015-06-10 Kay Brandner , Michael Bauer , Michael T. Schmid , Udo Seifert

We discuss the action principle and resulting Hamiltonian equations of motion for a class of integer-valued cellular automata introduced recently [1]. Employing sampling theory, these deterministic finite-difference equations are mapped…

Quantum Physics · Physics 2014-04-18 Hans-Thomas Elze

Capsule networks, which incorporate the paradigms of connectionism and symbolism, have brought fresh insights into artificial intelligence. The capsule, as the building block of capsule networks, is a group of neurons represented by a…

Quantum Physics · Physics 2022-12-19 Zidu Liu , Pei-Xin Shen , Weikang Li , L. -M. Duan , Dong-Ling Deng

Quantum simulation is a promising near term application for mesoscale quantum information processors, with the potential to solve computationally intractable problems at the scale of just a few dozen interacting quantum systems. Recent…

Quantum Physics · Physics 2014-08-14 David L. Hayes , Steven T. Flammia , Michael J. Biercuk

We offer an alternative to the conventional network formulation of quantum computing. We advance the analog approach to quantum logic gate/circuit construction. As an illustration, we consider the spatially extended NOT gate as the first…

Quantum Physics · Physics 2014-11-18 Dima Mozyrsky , Vladimir Privman , Steven P. Hotaling

In this paper, we study a model of quantum Markov chains that is a quantum analogue of Markov chains and is obtained by replacing probabilities in transition matrices with quantum operations. We show that this model is very suited to…

Quantum Physics · Physics 2015-07-01 Lvzhou Li , Yuan Feng

Decoherence in Markovian systems can result indirectly from the action of a system Hamiltonian which is usually fixed and unavoidable. Here, we show that in general in Markovian systems, because of the system Hamiltonian, quantum…

Quantum Physics · Physics 2008-08-13 Manas K. Patra , Peter G. Brooke

In this note, we are concerned with dark modes in a class of non-Markovian open quantum systems. Based on a microscopic model, a time-convoluted linear quantum stochastic differential equation and an output equation are derived to describe…

Quantum Physics · Physics 2021-04-01 Shikun Zhang , Daoyi Dong , Kun Liu

Response functions are key observables for probing the structure and dynamics of many-body systems. We introduce and demonstrate a quantum-classical framework for computing response functions of general many-fermion systems that also…

Quantum Physics · Physics 2026-02-10 Weijie Du , Yangguang Yang , Zixin Liu , Chao Yang , James P. Vary

With the rapid advancement of quantum information technology, quantum networks have become essential for supporting diverse applications, which often have stringent demands for key metrics such as fidelity and request completion time. In…

Quantum Physics · Physics 2025-08-08 Yuan Li , Chen Zhang , Hao Zhang , Tao Huang , Yunjie Liu

We present equivalent circuits that model the interaction of microwave resonators and quantum systems. The circuit models are derived from a general interaction Hamiltonian. Quantitative agreement between the simulated resonator…

Quantum Physics · Physics 2011-06-20 Alpár Mátyás , Christian Jirauschek , Federico Peretti , Paolo Lugli , György Csaba