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Related papers: On the complexity of controlling quantum many-body…

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A quantum system subject to external fields is said to be controllable if these fields can be adjusted to guide the state vector to a desired destination in the state space of the system. Fundamental results on controllability are reviewed…

Nuclear Theory · Physics 2008-11-26 John W. Clark , Dennis G. Lucarelli , Tzyh-Jong Tarn

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

We introduce a new approach for the robust control of quantum dynamics of strongly interacting many-body systems. Our approach involves the design of periodic global control pulse sequences to engineer desired target Hamiltonians that are…

Quantum Physics · Physics 2020-07-08 Joonhee Choi , Hengyun Zhou , Helena S. Knowles , Renate Landig , Soonwon Choi , Mikhail D. Lukin

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

We consider the dynamics of continuously measured many-body chaotic quantum systems. Focusing on the observable of state purification, we analytically describe the limits of strong and weak measurement rate, where in the latter case…

Disordered Systems and Neural Networks · Physics 2022-07-15 A. Altland , M. Buchhold , S. Diehl , T. Micklitz

Dynamical measurement schemes are an important tool for the investigation of quantum many-body systems, especially in the age of quantum simulation. Here, we address the question whether generic measurements can be implemented efficiently…

Quantum Physics · Physics 2018-08-29 Thomas Barthel , Jianfeng Lu

Time reversal in a macroscopic system is contradicting daily experience. It is practically impossible to restore a shattered cup to its original state by just time reversing the microscopic dynamics that led to its breakage. Yet, with the…

The NMR technique allows one to create a non-equilibrium local polarization and to detect its later evolution. By a change of the sign of the effective dipolar Hamiltonian, the apparently diffusive dynamics is reverted, generating a…

Condensed Matter · Physics 2007-05-23 Gonzalo Usaj , Horacio M. Pastawski , Patricia R. Levstein

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

Recent years have seen significant advances, both theoretical and experimental, in our understanding of quantum many-body dynamics. Given this problem's high complexity, it is surprising that a substantial amount of this progress can be…

Statistical Mechanics · Physics 2026-04-21 Bruno Bertini , Pieter W. Claeys , Tomaž Prosen

Methods that are devised to achieve reversal of quantum dynamics in time have been named "quatum time mirrors". Such a time mirror can be considered as a generalization of Hahn's spin echo to systems with continuous degrees of freedom. We…

Mesoscale and Nanoscale Physics · Physics 2018-10-03 Phillipp Reck , Cosimo Gorini , Klaus Richter

Recent progress in quantum physics has made it possible to perform experiments in which individual quantum systems are monitored and manipulated in real time. The advent of such new technical capabilities provides strong motivation for the…

Quantum Physics · Physics 2016-11-18 Andrew Doherty , John Doyle , Hideo Mabuchi , Kurt Jacobs , Salman Habib

Controllability properties for discrete-time, Markovian quantum dynamics are investigated. We find that, while in general the controlled system is not finite-time controllable, feedback control allows for arbitrary asymptotic state-to-state…

Quantum Physics · Physics 2012-10-25 Francesca Albertini , Francesco Ticozzi

Identifying the real and imaginary parts of wave functions with coordinates and momenta, quantum evolution may be mapped onto a classical Hamiltonian system. In addition to the symplectic form, quantum mechanics also has a positive-definite…

Quantum Physics · Physics 2009-11-07 R. Vilela Mendes , V. I. Man'ko

Optimal quantum control of continuous variable systems poses a formidable computational challenge because of the high-dimensional character of the system dynamics. The framework of quantum invariants can significantly reduce the complexity…

In spin systems, the decay of the Loschmidt echo in the time-reversal experiment (evolution, perturbation, time-reversed evolution) is linked to the generation of multiple-quantum coherences. The approach is extended to other systems, and…

Quantum Physics · Physics 2015-11-11 A. K. Khitrin

For a class of integrable quantum many-body systems, symmetric AC driving can generically produce a steady DC response. We show how such dynamical freezing can be switched off, not by forcing the system to follow the (arbitrarily fast)…

Statistical Mechanics · Physics 2012-08-02 Arnab Das , R. Moessner

We present an efficient strategy for controlling a vast range of non-integrable quantum many body one-dimensional systems that can be merged with state-of-the-art tensor network simulation methods like the density Matrix Renormalization…

Quantum Physics · Physics 2015-03-13 Patrick Doria , Tommaso Calarco , Simone Montangero

State-of-the-art quantum simulators permit local temporal control of interactions and midcircuit readout. These capabilities open the way towards the exploration of intriguing nonequilibrium phenomena. We illustrate this with a kinetically…

Quantum Physics · Physics 2025-06-12 Marcel Cech , María Cea , Mari Carmen Bañuls , Igor Lesanovsky , Federico Carollo

We study feedback control of classical Hamiltonian systems with the controlling parameter varying slowly in time. The control aims to change system's energy. We show that the control problems can be solved with help of an adiabatic…

Other Condensed Matter · Physics 2007-05-23 A. E. Allahverdyan , K. G. Petrosyan , D. B. Saakian