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We present a theoretical method to generate a highly accurate {\em time-independent} Hamiltonian governing the finite-time behavior of a time-periodic system. The method exploits infinitesimal unitary transformation steps, from which…

Statistical Mechanics · Physics 2019-05-30 Michael Vogl , Pontus Laurell , Aaron D. Barr , Gregory A. Fiete

Braiding of Majorana zero modes provides a promising platform for quantum information processing, which is topologically protected against errors. Strictly speaking, however, the scheme relies on infinite braiding times as it utilizes the…

Mesoscale and Nanoscale Physics · Physics 2015-05-18 Torsten Karzig , Armin Rahmani , Felix von Oppen , Gil Refael

Transferring the state of a quantum system to a given distribution of populations is an important problem with applications to Quantum Chemistry and Atomic Physics. In this work we consider exact population transfers that minimize the L^2…

Quantum Physics · Physics 2007-05-23 Symeon Grivopoulos , Bassam Bamieh

We consider a time-dependent small quantum system weakly coupled to an environnement, whose effective dynamics we address by means of a Lindblad equation. We assume the Hamiltonian part of the Lindbladian is slowly varying in time and the…

Mathematical Physics · Physics 2022-02-16 Alain Joye

We introduce an adiabatic state preparation protocol which implements quantum imaginary time evolution under the Hamiltonian of the system. Unlike the original quantum imaginary time evolution algorithm, adiabatic quantum imaginary time…

Quantum Physics · Physics 2024-04-23 Kasra Hejazi , Mario Motta , Garnet Kin-Lic Chan

We study time-optimal protocols for controlling quantum systems which show several avoided level crossings in their energy spectrum. The structure of the spectrum allows us to generate a robust guess which is time-optimal at each crossing.…

Quantum Physics · Physics 2015-11-18 P. M. Poggi , F. C. Lombardo , D. A. Wisniacki

To optimize the performance of a heat engine in finite-time cycle, it is important to understand the finite-time effect of thermodynamic processes. Previously, we have shown that extra work is needed to complete a quantum adiabatic process…

Quantum Physics · Physics 2019-10-09 Jin-Fu Chen , Chang-Pu Sun , Hui Dong

Using the adiabatic perturbation theory of driven dynamics [Phys. Rev. A 78, 052508 (2008)] we design a hierarchy of quantum state preparation protocols that systematically increase the fidelity at very long driving times. We test these and…

Quantum Physics · Physics 2023-02-01 Felipe Matus , Jan Střeleček , Pavel Stránský , Pavel Cejnar

Optimal control theory is applied to analyze the time-optimal solution with a single scalar control knob in a two-level quantum system without quantum decoherence. Emphasis is \change{placed} on the dependence on the maximum control…

Quantum Physics · Physics 2025-04-03 Chungwei Lin , Qi Ding , Petros T. Boufounos , Yanting Ma , Yebin Wang , Dries Sels , Chih-Chun Chien

Adiabatic evolution is considered to be the ideal situation for most thermodynamic cycles, as it allows for the achievement of maximum efficiency. However, no power output is produced in light of the infinite amount of time required to…

Quantum Physics · Physics 2020-02-17 Qiongyuan Wu , Giovanni Barontini , Mauro Paternostro

The overdamped Brownian dynamics of a harmonic oscillator is a paradigmatic system in non-equilibrium statistical mechanics, which reliably models relevant stochastic systems such as colloidal particles submitted to optical confinement. In…

Statistical Mechanics · Physics 2022-09-08 Antonio Patrón , Antonio Prados , Carlos A. Plata

Advances in quantum algorithms suggest a tentative scaling advantage on certain combinatorial optimization problems. Recent work, however, has also reinforced the idea that barren plateaus render variational algorithms ineffective on large…

Quantum Physics · Physics 2025-03-14 Tim Bode , Krish Ramesh , Tobias Stollenwerk

Efficient control schemes that enable fast, high-fidelity operations are essential for any practical quantum computation. However, current optimization protocols are intractable due to stringent requirements imposed by the microscopic…

Quantum Physics · Physics 2025-11-13 Christian Ventura Meinersen , Stefano Bosco , Maximilian Rimbach-Russ

We apply the method of transitionless quantum driving for time-dependent quantum systems to spin systems. For a given Hamiltonian, the driving Hamiltonian is constructed so that the adiabatic states of the original system obey the…

Quantum Physics · Physics 2013-06-14 Kazutaka Takahashi

The adiabatic approximation in open systems is formulated through the effective Hamiltonian approach. By introducing an ancilla, we embed the open system dynamics into a non-Hermitian quantum dynamics of a composite system, the adiabatic…

Quantum Physics · Physics 2009-11-13 X. X. Yi , D. M. Tong , L. C. Kwek , C. H. OH

Information processing, quantum or classical, relies on channels transforming multiple input states to different corresponding outputs. Previous research has established bounds on the thermodynamic resources required for such operations,…

Quantum Physics · Physics 2024-05-22 Joe Dunlop , Federico Cerisola , Jorge Tabanera-Bravo , Janet Anders

The optimal control problem for open quantum systems can be formulated as a time-dependent Lindbladian that is parameterized by a number of time-dependent control variables. Given an observable and an initial state, the goal is to tune the…

Quantum Physics · Physics 2024-05-30 Wenhao He , Tongyang Li , Xiantao Li , Zecheng Li , Chunhao Wang , Ke Wang

We review recent progress in optimal control in stochastic thermodynamics. Theoretical advances provide in-depth insight into minimum-dissipation control with either full or limited (parametric) control, and spanning the limits from slow to…

Statistical Mechanics · Physics 2023-04-13 Steven Blaber , David A. Sivak

Chemical relaxation phenomena, including photochemistry and electron transfer processes, form a vigorous area of research in which nonadiabatic dynamics plays a fundamental role. Here, we show that for nonadiabatic dynamics with two…

Chemical Physics · Physics 2022-07-20 Yanze Wu , Xuezhi Bian , Jonathan Rawlinson , Robert G. Littlejohn , Joseph E. Subotnik

The number of defects which are generated on crossing a quantum phase transition can be minimized by choosing properly designed time-dependent pulses. In this work we determine what are the ultimate limits of this optimization. We discuss…

Other Condensed Matter · Physics 2015-05-20 T. Caneva , T. Calarco , R. Fazio , G. E. Santoro , S. Montangero