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Correction: Morzhin, O.V.; Pechen, A.N. Control of the von Neumann Entropy for an Open Two-Qubit System Using Coherent and Incoherent Drives. <i>Entropy</i> 2024, <i>26</i>, 36.

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Control of the von Neumann Entropy for an Open Two-Qubit System Using Coherent and Incoherent Drives.

Oleg V Morzhin¹, Alexander N Pechen¹

¹Department of Mathematical Methods for Quantum Technologies & Steklov International Mathematical Center, Steklov Mathematical Institute of Russian Academy of Sciences, 8 Gubkina Str., 119991 Moscow, Russia

Entropy (Basel, Switzerland)

|January 22, 2024

Summary

This summary is machine-generated.

Researchers developed methods to control the von Neumann entropy (S) of quantum systems. This research enables precise manipulation of quantum states by managing decoherence rates in two-qubit systems.

Keywords:

coherent control incoherent control open quantum system optimization methods quantum control quantum thermodynamics two-qubit system von Neumann entropy

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Area of Science:

Quantum Information Science
Quantum Control Theory
Open Quantum Systems

Background:

Understanding and controlling quantum states is crucial for quantum technologies.
The von Neumann entropy quantifies the uncertainty or mixedness of a quantum state.
Open quantum systems experience decoherence, affecting their dynamics and controllability.

Purpose of the Study:

To develop an approach for manipulating the von Neumann entropy of an open two-qubit system.
To explore various control objectives including minimization, maximization, target steering, and state constraint satisfaction.
To investigate the impact of coherent and incoherent controls on entropy dynamics.

Main Methods:

Utilized Markovian dynamics described by a Gorini-Kossakowski-Sudarshan-Lindblad master equation.
Adapted one- and two-step gradient projection methods for optimization.
Employed a genetic algorithm to address the control challenges.

Main Results:

Successfully adapted optimization algorithms to manipulate von Neumann entropy under time-dependent decoherence.
Demonstrated numerical results for various entropy manipulation goals (minimization, maximization, target steering, constraint satisfaction).
Showcased the effectiveness of combined coherent and incoherent controls.

Conclusions:

The proposed approach provides a robust framework for controlling the entropy of open two-qubit systems.
The adapted numerical methods are effective for achieving specific entropy manipulation objectives.
This work contributes to the advancement of quantum state engineering and control.