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

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Quantum key distribution (QKD) offers a reliable solution to communication problems that require long-term data security. For its widespread use, however, the rate and reach of QKD systems must be improved. Twin-field (TF) QKD is a step…

Fluxonium qubits combine long coherence times with strong anharmonicity, making them a promising platform for scalable superconducting quantum processors. Recent experiments have demonstrated high-fidelity operations in multi-qubit…

Quantum Physics · Physics 2026-04-30 Guo Xuan Chan , Wangwei Lan , Tenghui Wang , Xizheng Ma , Chunqing Deng , Lijing Jin

The stabilization of quantum states is a fundamental problem for realizing various quantum technologies. Measurement-based-feedback strategies have demonstrated powerful performance, and the construction of quantum control signals using…

Systems and Control · Electrical Eng. & Systems 2026-04-10 Chunxiang Song , Yanan Liu , Daoyi Dong , Hidehiro Yonezawa

We study the robustness of the evolution of a quantum system against small uncontrolled variations in parameters in the Hamiltonian. We show that the fidelity susceptibility, which quantifies the perturbative error to leading order, can be…

Quantum Physics · Physics 2024-05-09 Pablo M. Poggi , Gabriele De Chiara , Steve Campbell , Anthony Kiely

In classical control theory, tracking refers to the ability to perform measurements and feedback on a classical system in order to enforce some desired dynamics. In this paper we investigate a simple version of quantum tracking, namely, we…

Quantum Physics · Physics 2008-11-20 Paulo E. M. F. Mendonca , Alexei Gilchrist , Andrew C. Doherty

The purpose of this paper is to present a theoretic and numerical study of utilizing squeezing and phase shift in coherent feedback control of linear quantum optical systems. A quadrature representation with built-in phase shifters is…

Quantum Physics · Physics 2012-06-19 Guofeng Zhang , Heung Wing Joseph Lee , Bo Huang , Hu Zhang

This work develops measures for quantifying the effects of field noise upon targeted unitary transformations. Robustness to noise is assessed in the framework of the quantum control landscape, which is the mapping from the control to the…

The kinematics of many nonlinear control systems, especially in the robotics field, admit a transitive Lie-group symmetry, which is useful in high performance observer design. The recently proposed equivariant filter (EqF) exploits…

Systems and Control · Electrical Eng. & Systems 2022-09-13 Yixiao Ge , Pieter van Goor , Robert Mahony

Rate processes are simple and analytically tractable models for many dynamical systems which switch stochastically between a discrete set of quasi stationary states but they may also approximate continuous processes by coarse grained,…

Statistical Mechanics · Physics 2013-03-11 R. Toenjes , H. Kori

Quantum feedback is a technique for measuring a qubit and applying appropriate feedback depending on the measurement results. Here, we propose a new on-chip quantum feedback method where the measurement-result information is not taken from…

Quantum Physics · Physics 2015-09-03 K. Kakuyanagi , A. Kemp , T. Baba , Y. Matsuzaki , H. Nakano , K. Semba , S. Saito

This paper addresses the design of robust dynamic output feedback control for highly uncertain systems in which the unknown disturbance might be excited by the derivative of the control input. This context appears in many industrial…

Systems and Control · Computer Science 2016-10-20 Mazen Alamir , Jean Dobrowolski , Amgad tarek Mohammed

Fastness and robustness are both critical in the implementation of high-fidelity gates for quantum computation, but in practice, a trade-off has to be made between them. In this paper, we investigate the underlying robust time-optimal…

Quantum Physics · Physics 2023-09-12 Xi Cao , Jiangyu Cui , Man Hong Yung , Re-Bing Wu

Two-level systems are one of the most important quantum systems and they form the basis of quantum computers. We briefly look at the traditional approach to two-level systems with an external driving field as well as those subjected to…

Quantum Physics · Physics 2016-09-14 Rajath Krishna R , N. S. Vidhyadhiraja

We experimentally study the time-optimal construction of arbitrary single-qubit rotations under a single strong driving field of finite amplitude. Using radiation-dressed states of nitrogen vacancy centers in diamond, we realize a…

Quantum Physics · Physics 2014-07-02 Chen Avinadav , Ran Fischer , Paz London , David Gershoni

This paper proposed a framework based on quantum computing for reliability assessment of complex systems. The 'Quantum Twin' concept was also proposed. The framework can be used to accelerate the reliability assessment of large-scale…

Systems and Control · Electrical Eng. & Systems 2021-04-07 Shutang You

Robust control of quantum systems is an increasingly relevant field of study amidst the second quantum revolution, but there remains a gap between taming quantum physics and robust control in its modern analytical form that culminated in…

The Rate Control Protocol (RCP) uses explicit feedback from routers to control network congestion. RCP estimates it's fair rate from two forms of feedback: rate mismatch and queue size. An important design question that remains open in RCP…

Networking and Internet Architecture · Computer Science 2020-04-22 Abuthahir Abuthahir , Nizar Malangadan , Gaurav Raina

Quantum entanglement plays a fundamental role in quantum computation and quantum communication. Feedback control has been widely used in stochastic quantum systems to generate given entangled states since it has good robustness, where the…

Quantum Physics · Physics 2023-07-28 Yanan Liu , Daoyi Dong , Sen Kuang , Ian R. Petersen , Hidehiro Yonezawa

Specific low-bitrate coding strategies are examined through their effect on LQ control performance. By limiting the subject to these methods, we are able to identify principles underlying coding for control; a subject of significant recent…

Optimization and Control · Mathematics 2020-04-09 Behrooz Amini , Robert R. Bitmead

A density matrix approach is developped for the control of a mixed-state quantum system using a time-dependent external field such as a train of pulses. This leads to the definition of a target density matrix constructed in a reduced…

Quantum Physics · Physics 2007-05-23 D. Sugny , A. Keller , O. Atabek , D. Daems , C. M. Dion , S. Guérin , H. R. Jauslin