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Related papers: Quantum Control at the Boundary: an application to…

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Simulating quantum mechanics is known to be a difficult computational problem, especially when dealing with large systems. However, this difficulty may be overcome by using some controllable quantum system to study another less controllable…

Quantum Physics · Physics 2014-03-14 I. M. Georgescu , S. Ashhab , Franco Nori

Quantum phase transitions encompass a variety of phenomena that occur in quantum systems exhibiting several possible symmetries. Traditionally, these transitions are explored by continuously varying a control parameter that connects two…

Quantum Physics · Physics 2024-06-12 Á. Sáiz , J. Khalouf-Rivera , J. M. Arias , P. Pérez-Fernández , J. Casado-Pascual

Optimal control can be used to significantly improve multi-qubit gates in quantum information processing hardware architectures based on superconducting circuit quantum electrodynamics. We apply this approach not only to dispersive gates of…

Quantum Physics · Physics 2015-05-14 R. Fisher , F. Helmer , S. J. Glaser , F. Marquardt , T. Schulte-Herbrueggen

Manipulation of infinite dimensional quantum systems is important to controlling complex quantum dynamics with many practical physical and chemical backgrounds. In this paper, a general investigation is casted to the controllability problem…

Quantum Physics · Physics 2009-11-11 Re-Bing Wu , Tzyh-Jong Tarn , Chun-Wen Li

We propose a technique to design control algorithms for a class of finite dimensional quantum systems so that the control law does not present discontinuities. The class of models considered admits a group of symmetries which allows us to…

Quantum Physics · Physics 2019-10-23 Domenico D'Alessandro , Benjamin Sheller

A precise time-dependent control of a quantum system relies on an accurate account of the quantum interference among the system, the control and the environment. A diagrammatic technique has been recently developed to precisely calculate…

Mesoscale and Nanoscale Physics · Physics 2015-05-30 Ching-Kit Chan , L. J. Sham

We present a method for optimizing quantum control in experimental systems, using a subset of randomized benchmarking measurements to rapidly infer error. This is demonstrated to improve single- and two-qubit gates, minimize gate…

In our model a fixed Hamiltonian acts on the joint Hilbert space of a quantum system and its controller. We show under which conditions measurements, state preparations, and unitary implementations on the system can be performed by quantum…

Quantum Physics · Physics 2009-11-07 Dominik Janzing , Frederik Armknecht , Robert Zeier , Thomas Beth

We investigate the control resources needed to effect arbitrary quantum dynamics. We show that the ability to perform measurements on a quantum system, combined with the ability to feed back the measurement results via coherent control,…

Quantum Physics · Physics 2007-05-23 Seth Lloyd , Lorenza Viola

We describe how one may go about performing quantum computation with arbitrary "quantum stuff", as long as it has some basic physical properties. Imagine a long strip of stuff, equipped with regularly spaced wires to provide input settings…

Quantum Physics · Physics 2019-12-03 Lucien Hardy , Adam G. M. Lewis

We exploit the concept of Landau-Zener transitions at avoided energy crossings as a quantum-control tool. In an avoided crossing the two quantum states interchange their characteristics as an external parameter is varied. Depending on the…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 D. A. Wisniacki , G. E. Murgida , P. I. Tamborenea

An essential element of classical computation is the "if-then" construct, that accepts a control bit and an arbitrary gate, and provides conditional execution of the gate depending on the value of the controlling bit. On the other hand,…

Quantum Physics · Physics 2016-09-02 Alessandro Bisio , Michele Dall'Arno , Paolo Perinotti

Using the semigroup approach to abstract boundary control problems we characterize the space of all exactly reachable states. Moreover, we study the situation when the controls of the system are required to be positive. The abstract results…

Functional Analysis · Mathematics 2017-12-11 Klaus-Jochen Engel , Marjeta Kramar Fijavž

Quantum control is traditionally expressed through bilinear models and their associated Lie algebra controllability criteria. But, the first order approximation are not always sufficient and higher order developpements are used in recent…

Numerical Analysis · Mathematics 2008-08-14 Gabriel Turinici

Indirect controllability of an arbitrary finite dimensional quantum system (N-dimensional qudit) through a quantum accessor is investigated. Here, The qudit is coupled to a quantum accessor which is modeled as a fully controllable spin…

Quantum Physics · Physics 2009-11-13 H. C. Fu , Hui Dong , X. F. Liu , C. P. Sun

The paper is concerned with the boundary controllability of entropy weak solutions to hyperbolic systems of conservation laws. We prove a general result on the asymptotic stabilization of a system near a constant state. On the other hand,…

Optimization and Control · Mathematics 2007-05-23 Alberto Bressan , Giuseppe Maria Coclite

Structured decompositions of a desired unitary operator are employed to derive control schemes that achieve certain control objectives for finite-level quantum systems using only sequences of simple control pulses such as square waves with…

Quantum Physics · Physics 2007-05-23 S. G. Schirmer , A. D. Greentree , V. Ramakrishna , H. Rabitz

In this paper, we define the quotinet graphs. In particular, we introduce the boundary quotient graphs, admissible boundary quotient graphs and subgraph boundary qoutient graphs. By the property of the quotient spaces, the boundary…

Combinatorics · Mathematics 2007-05-23 Ilwoo Cho

Classical simulations of time-dependent quantum systems are widely used in quantum control research. In particular, these simulations are commonly used to host iterative optimal control algorithms. This is convenient for algorithms that are…

Quantum Physics · Physics 2021-11-23 Tyler Jones , Kaiah Steven , Xavier Poncini , Matthew Rose , Arkady Fedorov

The ability to manipulate quantum systems lies at the heart of the development of quantum technology. The ultimate goal of quantum control is to realize arbitrary quantum operations (AQuOs) for all possible open quantum system dynamics.…