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Related papers: A QFT approach to robust dual-rate control systems

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We propose and develop a measurement scheme for quantum field theory (QFT) in curved spacetimes, in which the QFT of interest, the "system", is dynamically coupled to another, the "probe", in a compact spacetime region. Measurements of…

General Relativity and Quantum Cosmology · Physics 2019-04-16 Christopher J. Fewster

Feedback is the core concept in cybernetics and its effective use has made great success in but not limited to the fields of engineering, biology, and computer science. When feedback is used to quantum systems, two major types of feedback…

Quantum Physics · Physics 2014-09-11 Bo Qi , Daoyi Dong , Chunlin Chen , Lijun Liu , Zairong Xi

Control of multi-level quantum systems is sensitive to implementation errors in the control field and uncertainties associated with system Hamiltonian parameters. A small variation in the control field spectrum or the system Hamiltonian can…

Quantum Physics · Physics 2015-06-23 Andy Koswara , Raj Chakrabarti

We present a multifractal analysis of time series data obtained by repeatedly running a single-qubit quantum circuit on IBM superconducting quantum computers, in which the measurement outcomes are recorded as the number of zeros. By…

Quantum Physics · Physics 2025-12-23 Mohammadreza Saghafi , Lamine Mili , Karlton Wirsing

Phase transitions have recently been formulated in the time domain of quantum many-body systems, a phenomenon dubbed dynamical quantum phase transitions (DQPTs), whose phenomenology is often divided in two types. One refers to distinct…

Quantum Physics · Physics 2021-01-04 Ricardo Puebla

Superconducting quantum technologies require qubit systems whose properties meet several often conflicting requirements, such as long coherence times and high anharmonicity. Here, we provide an engineering framework based on a generalized…

Pointlike systems coupled to quantum fields are often employed as toy models for measurements in quantum field theory. In this paper, we identify the field observables recorded by such models. We show that in models that work in the strong…

Quantum Physics · Physics 2023-08-29 Maria Papageorgiou , Jose de Ramon , Charis Anastopoulos

No mixed research of hybrid and fractional-order systems into a cohesive and multifaceted whole can be found in the literature. This paper focuses on such a synergistic approach of the theories of both branches, which is believed to give…

Systems and Control · Computer Science 2014-07-25 S. Hassan HosseinNia , Ines Tejado , Blas M. Vinagre

Double quantum dots are one of the promising two-state quantum systems for realizing qubits. In the quest of successfully manipulating and reading information in qubit systems, it is of prime interest to control the charge response of the…

Mesoscale and Nanoscale Physics · Physics 2022-10-04 A. Crépieux , M. Lavagna

Closed loop quantum control uses measurement to control the dynamics of a quantum system to achieve either a desired target state or target dynamics. In the case when the quantum Hamiltonian is quadratic in ${x}$ and ${p}$, there are known…

Quantum Physics · Physics 2021-11-15 Sangkha Borah , Bijita Sarma , Michael Kewming , Gerard J. Milburn , Jason Twamley

This paper considers the optimization landscape of linear dynamic output feedback control with $\mathcal{H}_\infty$ robustness constraints. We consider the feasible set of all the stabilizing full-order dynamical controllers that satisfy an…

Optimization and Control · Mathematics 2023-07-07 Bin Hu , Yang Zheng

We demonstrate and contrast two approaches to the stabilization of qubit entanglement by feedback. Our demonstration is built on a feedback platform consisting of two superconducting qubits coupled to a cavity which are measured by a…

Quantum gates (unitary gates) on physical systems are usually implemented by controlling the Hamiltonian dynamics. When full descriptions of the Hamiltonians parameters is available, the set of implementable quantum gates is easily…

Quantum Physics · Physics 2019-10-16 Ryosuke Sakai , Akihito Soeda , Mio Murao , Daniel Burgarth

Discrete quantum feedback control consists of a managed dynamics according to the information acquired by a previous measurement. Energy fluctuations along such dynamics satisfy generalized fluctuation relations, which are useful tools to…

Quantum Physics · Physics 2018-05-04 Patrice A. Camati , Roberto M. Serra

The quality of control (QoC) of a resource-constrained embedded control system may be jeopardized in dynamic environments with variable workload. This gives rise to the increasing demand of co-design of control and scheduling. To deal with…

Other Computer Science · Computer Science 2008-12-18 Feng Xia , Youxian Sun , Yu-Chu Tian , Moses Tade , Jinxiang Dong

To control a quantum system via feedback, we generally have two options in choosing control scheme. One is the coherent feedback, which feeds the output field of the system, through a fully quantum device, back to manipulate the system…

Quantum Physics · Physics 2014-11-19 Naoki Yamamoto

We revisit the problem of switching off unwanted phase evolution and decoherence in a single two-state quantum system in the light of recent results on random dynamical decoupling methods [L. Viola and E. Knill, Phys. Rev. Lett. {\bf 94},…

Quantum Physics · Physics 2009-11-11 Lea F. Santos , Lorenza Viola

We exploit a novel approximation scheme to obtain a new and compact formula for the parameters underlying coherent-state control of the evolution of a pair of entangled two-level systems. It is appropriate for long times and for relatively…

Quantum Physics · Physics 2010-08-24 Muhammed Yonac , Joseph H. Eberly

Quantum Field Theory (QFT) makes predictions by combining assumptions about (1) quantum dynamics, typically a Schrodinger or Liouville equation; (2) quantum measurement, usually via a collapse formalism. Here I define a "classical density…

Quantum Physics · Physics 2007-05-23 Paul J. Werbos

The problem of robust distributed control arises in several large-scale systems, such as transportation networks and power grid systems. In many practical scenarios controllers might not have enough information to make globally optimal…

Systems and Control · Computer Science 2019-09-26 Luca Furieri , Maryam Kamgarpour