The Q-Safe Project
The Q-Safe project aims to investigate the use of classical methods from control and learning to improve quantum information processing. To this end, we address various aspects of quantum theory such as feedback protocols for variational quantum algorithms and control and estimation of continuously monitored quantum systems.
Recent publications:
H. G. Clausen, P. Rouchon, and R. Wisniewski, “Online Parameter Estimation for Continuously-Monitored Quantum Systems.” IEEE Control Systems Letters, May 2024. doi: 10.1109/LCSYS.2024.3407608.
H. G. Clausen, S. A. Rahman, Ö. Karabacak, and R. Wisniewski, “Measurement-Based Control for Minimizing Energy Functions in Quantum Systems,” IFAC-PapersOnLine, vol. 56, no. 2, pp. 5171–5178, Nov. 2023, doi: 10.1016/j.ifacol.2023.10.111.
Henrik G. Clausen PhD fellow
Estimation and control of continuously monitored quantum systems
When quantum systems are subject to repeated or continuous measurements, the resulting dynamics may be described by a stochastic master equation. In this project, we study how the classical measurement signal available in such models may be used for stabilization of exotic quantum states and for real-time estimation of unknown dynamical parameters. To this end, we rely on techniques from stochastic systems, nonlinear control and optimization.
Salahuddin A. Rahman
PhD fellow
Quantum Algorithms for Optimization
Research objective:
To design hybrid quantum-classical algorithms for preparing eigenstates of Hamiltonians inspired by quantum control theory.
Tools and methods:
Quantum Lyapunov Control (Lyapunov stability, invariance principle).
Digital Quantum Simulation (Trotterized time evolution).
Quantum algorithms (Expectation estimation algorithms, overlap estimation algorithms, parameter-shift-rule, warm starting algorithms).
Recent publications:
Rahman, S.A., Karabacak, Ö. and Wisniewski, R., 2024. “Feedback-Based Quantum Algorithm for Constrained Optimization Problems.” Accepted for publication in the PPAM 2024 conference.
doi: https://arxiv.org/abs/2406.08169
Rahman, S.A., Karabacak, Ö. and Wisniewski, R., 2024. “Weighted Feedback-Based Quantum Algorithm for Excited States Calculation.” arXiv preprint arXiv:2404.19386. Accepted for publication in the QCE 2024 conference. doi: https://doi.org/10.48550/arXiv.2404.19386
Rahman, S.A., Clausen, H.G., Karabacak, Ö. and Wisniewski, R., 2024, June. “Adaptive Sampling Noise Mitigation Technique for Feedback-Based Quantum Algorithms.” In International Conference on Computational Science (pp. 321-329). Cham: Springer Nature Switzerland.
Rahman, S.A., Karabacak, Ö. and Wisniewski, R., 2024. “Feedback-Based Quantum Algorithm for Excited States Calculation.” arXiv preprint arXiv:2404.04620. doi: https://doi.org/10.48550/arXiv.2404.04620
Recent publications:
N. B. Dehaghani, A. P. Aguiar, and R. Wisniewski, "A Hybrid Quantum-Classical Physics-Informed Neural Network Architecture for Solving Quantum Optimal Control Problems." Apr. 2024. arXiv preprint arXiv:2404.15015. (Submitted for publication)
N. B. Dehaghani, A. P. Aguiar, and R. Wisniewski, "Enhancing Quantum Entanglement in Bipartite Systems: Leveraging Optimal Control and Physics-Informed Neural Networks." Mar. 2024. arXiv preprint arXiv:2403.16321. (Submitted for publication)
N. B. Dehaghani, A. P. Aguiar, and R. Wisniewski, “Stochastic Quantum Dynamics Stabilization: A Lyapunov-Based Control Approach with Homodyne-Mediated Filtering." Mar. 2024. arXiv preprint arXiv:2403.07021. (Submitted for publication)
N. B. Dehaghani, A. P. Aguiar, and R. Wisniewski, "Quantum Pontryagin Neural Networks in Gamkrelidze Form Subjected to the Purity of Quantum Channels." IEEE Control Systems Letters (LCSS-CDC), Jun. 2023. doi: 10.1109/LCSYS.2023.3286303.
Nahid Binadeh Dehaghani PhD student University of Porto
Computational Methods for Optimal Quantum Control
Optimal control of quantum systems is essential for the development of efficient quantum information processing. To this end, we study new computational methods based on physics-informed neural networks for computing optimal controls for open quantum systems subject to constraints such as decoherence effects.
Contact Us
Prof. Rafal Wisniewski
Henrik G. Clausen
Salahuddin A.Rahman
