🤖 AI Summary
This study addresses the modeling challenges of many-body quantum systems, which are inherently nonlinear, history-dependent, and computationally expensive to simulate. To this end, we propose a Dissipative Quantum Reservoir Computing (DQRC) framework. This approach leverages a fixed, small-scale open quantum system as a digital twin, requiring only the training of a classical readout layer to directly learn input-output mappings, thereby enabling a physically realizable and compact architecture. Experimental results demonstrate that a minimal reservoir based on a single qubit can reproduce the high-harmonic responses of large-scale systems. Furthermore, the proposed method outperforms conventional models while exhibiting strong generalization capabilities. Overall, this work presents an efficient new paradigm for modeling complex quantum dynamics.
📝 Abstract
Modeling the response of driven many-body quantum systems from input--output data is difficult: the dynamics are nonlinear, history dependent, and expensive to simulate as system size grows. A paradigmatic case is High-Harmonic Generation~(HHG), where a strong field drives a medium to emit radiation that is highly sensitive to the drive and encodes long-range temporal correlations. We introduce a dissipative quantum reservoir computing~(DQRC) framework that builds a digital twin of such a system, learning its input--output map directly from data while the reservoir---itself a small open quantum system---stays fixed and only a classical readout is trained. We show that a minimal single-qubit reservoir reproduces the HHG response of a substantially larger Ising spin chain, and on a representative benchmark matches and on several metrics surpasses previously reported temporal convolutional and Kolmogorov--Arnold-network models, while using a simpler, physically realizable system. A single fixed reservoir further generalizes across a broad range of drives, indicating that it learns a shared physical response structure rather than memorizing trajectories. These results establish dissipative quantum reservoirs as compact, physically grounded digital twins for nonlinear, memory-dependent quantum dynamics.
Code is available at \href{https://github.com/AI-and-Quantum-Computing/DQuRC}{https://github.com/AI-and-Quantum-Computing/DQuRC}.