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Related papers: Local controllability of quantum networks

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In this work we focus on a recently introduced method [1] to construct the external potential $v$ that, for a given initial state, produces a prescribed time-dependent density in an interacting quantum many-body system. We show how this…

Quantum Physics · Physics 2014-12-12 S. E. B. Nielsen , M. Ruggenthaler , R. van Leeuwen

Universal quantum computation requires the implementation of arbitrary control operations on the quantum register. In most cases, this is achieved by external control fields acting selectively on each qubit to drive single-qubit operations.…

Quantum Physics · Physics 2015-06-19 Jingfu Zhang , Daniel Burgarth , Raymond Laflamme , Dieter Suter

What interactions are sufficient to simulate arbitrary quantum dynamics in a composite quantum system? We provide an efficient algorithm to simulate any desired two-body Hamiltonian evolution using any fixed two-body entangling n-qubit…

Quantum Physics · Physics 2009-11-07 Jennifer L. Dodd , Michael A. Nielsen , Michael J. Bremner , Robert T. Thew

We study the problem of learning the Hamiltonian of a many-body quantum system from experimental data. We show that the rate of learning depends on the amount of control available during the experiment. We consider three control models: one…

Quantum Physics · Physics 2024-11-27 Alicja Dutkiewicz , Thomas E. O'Brien , Thomas Schuster

Quantum coherence inherently affects the dynamics and the performances of a quantum machine. Coherent control can, at least in principle, enhance the work extraction and boost the velocity of evolution in an open quantum system. Using…

Quantum Physics · Physics 2018-12-10 Vasco Cavina , Andrea Mari , Alberto Carlini , Vittorio Giovannetti

We show how one can implement any local quantum gate on specific qubits in an array of qubits by carrying adiabatically a Hamiltonian around a closed loop. We find the exact form of the loop and the Hamiltonian for implementing general one…

Quantum Physics · Physics 2009-11-10 Vahid Karimipour , Nayereh Majd

Understanding the microscopic mechanisms of thermalization in closed quantum systems is among the key challenges in modern quantum many-body physics. We demonstrate a method to probe local thermalization in a large-scale many-body system by…

We ask whether the knowledge of a single eigenstate of a local Hamiltonian is sufficient to uniquely determine the Hamiltonian. We present evidence that the answer is "yes" for generic local Hamiltonians, given either the ground state or an…

Quantum Physics · Physics 2019-07-10 Xiao-Liang Qi , Daniel Ranard

We address the problem of simulating pair-interaction Hamiltonians in n node quantum networks where the subsystems have arbitrary, possibly different, dimensions. We show that any pair-interaction can be used to simulate any other by…

Quantum Physics · Physics 2023-11-27 Pawel Wocjan , Martin Roetteler , Dominik Janzing , Thomas Beth

We provide sufficient conditions for the approximate controllability of infinite-dimensional quantum control systems corresponding to form perturbations of the drift Hamiltonian modulated by a control function. We rely on previous results…

Optimization and Control · Mathematics 2025-04-02 Aitor Balmaseda , Davide Lonigro , Juan Manuel Pérez-Pardo

Many-particle confinement (localization) is studied for a 1D system of spinless fermions with nearest-neighbor hopping and interaction, or equivalently, for an anisotropic Heisenberg spin-1/2 chain. This system is frequently used to model…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 M. I. Dykman , L. F. Santos , M. Shapiro

The precise implementation and manipulation of quantum gates is key to extracting advantages from future quantum technologies. Achieving this requires very accurate control over the quantum system. If one has complete knowledge about a…

Quantum Physics · Physics 2025-03-21 Anirban Dey , Mattias T. Johnsson , Daniel Burgarth

Generally, the local interactions in a many-body quantum spin system on a lattice do not commute with each other. Consequently, the Hamiltonian of a local region will generally not commute with that of the entire system, and so the two…

Quantum Physics · Physics 2016-04-11 Itai Arad , Tomotaka Kuwahara , Zeph Landau

Due to the presence of strong correlations, theoretical or experimental investigations of quantum many-body systems belong to the most challenging tasks in modern physics. Stimulated by tensor networks, we propose a scheme of constructing…

Strongly Correlated Electrons · Physics 2017-10-17 Shi-Ju Ran , Angelo Piga , Cheng Peng , Gang Su , Maciej Lewenstein

This paper discusses fully coherent quantum feedback control, in which the sensors, controller, and actuators are quantum systems and interact coherently with the system to be controlled: as a result, the entire feedback loop is coherent.…

Quantum Physics · Physics 2007-05-23 Seth Lloyd

Nanoscale engineered spin systems, ranging from spins on surfaces to nanographenes, provide flexible platforms to realize entangled quantum magnets from a bottom up approach. However, assessing the quantum many-body Hamiltonian realized in…

Mesoscale and Nanoscale Physics · Physics 2025-10-22 Netta Karjalainen , Greta Lupi , Rouven Koch , Adolfo O. Fumega , Jose L. Lado

We study a two-spin quantum Turing architecture, in which discrete local rotations \alpha_m of the Turing head spin alternate with quantum controlled NOT-operations. Substitution sequences are known to underlie aperiodic structures. We show…

Quantum Physics · Physics 2015-06-26 Ilki Kim , Guenter Mahler

Coherent control of quantum transitions -- indispensable in quantum technology -- generally relies on the interaction of quantum systems with electromagnetic radiation. Here, we theoretically demonstrate that the non-radiative…

Quantum Physics · Physics 2021-07-14 Dennis Rätzel , Daniel Hartley , Osip Schwartz , Philipp Haslinger

This work develops a quantum control application of many-body quantum chaos for ultracold bosonic gases trapped in optical lattices. It is long known how to harness exponential sensitivity to changes in initial conditions for control…

Identifying the nature of interactions in a quantum system is essential in understanding any physical phenomena. Acquiring information on the Hamiltonian can be a tough challenge in many-body systems because it generally requires access to…

Quantum Physics · Physics 2009-10-09 Daniel Burgarth , Koji Maruyama