Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Xitong kexue yu shuxue

CONVERGENCE OF STATE CONTROL OF OPEN QUANTUM SYSTEM IN DECOHERENCE-FREE SUBSPACES

Fei Yang

Published Jan 1, 2011• 0 citations
OpenAlex

Abstract

A convergent state control strategy of open quantum system based on Lyapunov method is proposed for the target state being a pure state in decoherence-free subspaces. Based on the assumptions of all the transition frequencies being different and all the levels being directly coupled,a sufficient condition is proposed for the observation operator to make that the largest invariant set only contains target state.On the basis of choosing the average of observable operators as a Lyapunov function,the control laws are designed in interaction picture and the largest invariant set of the controlled system is analyzed via Barbalat's Lemma. It is shown that any pure target state in decoherence-free subspace is globally asymptotic stable under the sufficient condition given,and the system controlled could be transferred to target state from arbitrary initial state.Also,a method is provided to construct the observation operator via Schmidt orthogonalization.Numerical experiments on a three-level system verify the validity of the proposed control strategy.

Related papers

Convergent control strategy of state in open quantum systems

Shuang Cong, Fei Yang

A control strategy of quantum states of open quantum system based on Lyapunov method is proposed. On the basis of choosing the average of observable operators as a Lyapunov function, the control laws are designed in interaction picture. We analyze the largest invariant set of the controlled system via Barbalat's Lemma. Based on some assumptions of Hamiltonians, we propose a sufficient condition of the observable operator to guarantee the convergence of the open quantum system, and proof that the proposed strategy can make any pure target state in decoherence-free subspace be globally asymptotic stable under the sufficient condition. Also, we provide a method to construct the observable operator via Schmidt orthogonalization. Numerical experiments on a three-level system validate the effectiveness of the proposed control strategy.

Chinese Control Conference (CCC)•Jul 22, 2011•0 citations

Control of quantum states in decoherence-free subspaces

Shuang Cong, Fei Yang

The problem of quantum state control in open quantum systems based on the Lyapunov method is studied. The control laws are designed to drive the system to a pure target state in decoherence-free subspace (DFS) in the interaction picture, where the average of an observable operator P is chosen as a Lyapunov function. By analyzing the positive limit set via Barbalat’s lemma, we propose a sufficient condition on the observable operator such that the positive limit set only contains the target state. Under this condition, it is proved that the control laws can drive the open system to any pure target state in DFS in the interaction picture. Also, we provide a method to construct the observable operator via Schmidt orthogonalization. Numerical simulations on a three-level system validate the effectiveness of the proposed control strategy.

Journal of Physics A Mathematical and Theoretical•Feb 4, 2013•14 citations

State transfer and coherence maintain based on DFS in open quantum systems

Shuang Cong, Jie Yang, Jianxiu Liu

To maintain state coherence in an open quantum systems, the decoherence-free subspace (DFS) is an effective method. The target state is usually needed to be in DFS. In the case the target state is not in DFS, we first design external control field I to construct a DFS included target state. Then another control field II is used to transfer the state of the system to be controlled to the expected target state. As is well known, invariant set contains all stable states of the system. Control Hamiltonian is designed to shrink invariant set and increase the transition probability from the system state to target state. In such a way, the state transfer and coherence maintain are completed. Numerical simulation is given for a four-level energy open quantum system to demonstrate the effectiveness of the control strategy proposed.

Chinese Control Conference (CCC)•Dec 24, 2012•0 citations

Path programming control strategy of quantum state transfer

Y. Lou, Shuang Cong, Jerry Zhijian Yang +1 more

The state transfer of closed quantum systems in the interaction picture is studied. The convergent problem encountered in designing control laws based on the Lyapunov method is solved by the well constructed observable operator and a path programming control strategy. It is proved that the condition for the target state being a stable point in the Lyapunov's sense is the coherent vectors of the observable operator and the target state must be in opposite directions. For the local optimisation limitation of the Lyapunov-based method, the path programming control strategy is proposed, which is used to change the distribution of stationary points or choose a transition path by appropriately selecting intermediate target states. Comparative numerical system simulation experiments are implemented on a four-level quantum system and the experimental results are analysed.

IET Control Theory and Applications•Jan 20, 2011•13 citations

Lyapunov stabilization strategy of mixed-state quantum systems with ideal conditions

Shuang Cong

Under the ideal conditions that the controlled systems are non-degenerate,transitionally non-degenerate,and fully connected,the stabilization problem of mixed-state quantum systems is studied by using a Lyapunov function with free degrees. Based on the LaSalle's principle,the largest invariant set of the closed-loop systems and the convergent state set associated with any initial state are deduced,and the construction principles of free degrees that ensure the system can be asymptotically stabilized in any equilibrium state contained in the largest invariant set are given. A numerical simulation experiment on a two-level system shows the rationality of the obtained theoretical results.

Kongzhi yu juece•Jan 1, 2010•4 citations

A Convergent Control Strategy for Quantum Systems

Shuang Cong, Yuesheng Lou, Jianxiu Liu +1 more

Abstract In the interaction picture, a sufficient and necessary condition that guarantees the convergence of closed quantum control system is proposed in this paper. Theoretical derivation and the proof show that it is possible to achieve the convergence to the target state by constructing an observable operator in an energy function and selecting control Hamiltonians. Numerical simulation experiments on a four-level system verify the effectiveness of the proposed control strategy.

arXiv:1402.6768•系统科学与信息学报(英文)•Jun 25, 2014•0 citations
A convergent state control strategy of open quantum system based on Lyapunov method is proposed for the target state being a pure state in decoherence-free subspaces. Based on the assumptions of all the transition frequencies being different and all the levels being directly coupled,a sufficient condition is proposed for the observation operator to make that the largest invariant set only contains target state.On the basis of choosing the average of observable operators as a Lyapunov function,the control laws are designed in interaction picture and the largest invariant set of the controlled system is analyzed via Barbalat's Lemma. It is shown that any pure target state in decoherence-free subspace is globally asymptotic stable under the sufficient condition given,and the system controlled could be transferred to target state from arbitrary initial state.Also,a method is provided to construct the observation operator via Schmidt orthogonalization.Numerical experiments on a three-level system verify the validity of the proposed control strategy.
A control strategy of quantum states of open quantum system based on Lyapunov method is proposed. On the basis of choosing the average of observable operators as a Lyapunov function, the control laws are designed in interaction picture. We analyze the largest invariant set of the controlled system via Barbalat's Lemma. Based on some assumptions of Hamiltonians, we propose a sufficient condition of the observable operator to guarantee the convergence of the open quantum system, and proof that the proposed strategy can make any pure target state in decoherence-free subspace be globally asymptotic stable under the sufficient condition. Also, we provide a method to construct the observable operator via Schmidt orthogonalization. Numerical experiments on a three-level system validate the effectiveness of the proposed control strategy.
The problem of quantum state control in open quantum systems based on the Lyapunov method is studied. The control laws are designed to drive the system to a pure target state in decoherence-free subspace (DFS) in the interaction picture, where the average of an observable operator P is chosen as a Lyapunov function. By analyzing the positive limit set via Barbalat’s lemma, we propose a sufficient condition on the observable operator such that the positive limit set only contains the target state. Under this condition, it is proved that the control laws can drive the open system to any pure target state in DFS in the interaction picture. Also, we provide a method to construct the observable operator via Schmidt orthogonalization. Numerical simulations on a three-level system validate the effectiveness of the proposed control strategy.
To maintain state coherence in an open quantum systems, the decoherence-free subspace (DFS) is an effective method. The target state is usually needed to be in DFS. In the case the target state is not in DFS, we first design external control field I to construct a DFS included target state. Then another control field II is used to transfer the state of the system to be controlled to the expected target state. As is well known, invariant set contains all stable states of the system. Control Hamiltonian is designed to shrink invariant set and increase the transition probability from the system state to target state. In such a way, the state transfer and coherence maintain are completed. Numerical simulation is given for a four-level energy open quantum system to demonstrate the effectiveness of the control strategy proposed.
The state transfer of closed quantum systems in the interaction picture is studied. The convergent problem encountered in designing control laws based on the Lyapunov method is solved by the well constructed observable operator and a path programming control strategy. It is proved that the condition for the target state being a stable point in the Lyapunov's sense is the coherent vectors of the observable operator and the target state must be in opposite directions. For the local optimisation limitation of the Lyapunov-based method, the path programming control strategy is proposed, which is used to change the distribution of stationary points or choose a transition path by appropriately selecting intermediate target states. Comparative numerical system simulation experiments are implemented on a four-level quantum system and the experimental results are analysed.
Under the ideal conditions that the controlled systems are non-degenerate,transitionally non-degenerate,and fully connected,the stabilization problem of mixed-state quantum systems is studied by using a Lyapunov function with free degrees. Based on the LaSalle's principle,the largest invariant set of the closed-loop systems and the convergent state set associated with any initial state are deduced,and the construction principles of free degrees that ensure the system can be asymptotically stabilized in any equilibrium state contained in the largest invariant set are given. A numerical simulation experiment on a two-level system shows the rationality of the obtained theoretical results.