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arXiv · 2501.15580

Connection between memory performance and optical absorption in quantum reservoir computing

Niclas Götting·Steffen Wilksen·Alexander Steinhoff·Frederik Lohof·Christopher Gies
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Abstract

The fading memory property is a key requirement for reservoir computers -- a specific type of recurrent neural network with fixed internal weights. While mostly undesired in gate-based quantum computing, dissipation due to material imperfections or coupling to the environment acts as a natural mechanism intrinsically providing fading memory to reservoir computers based on dynamical open quantum systems. In this work, we unravel a connection between the physical metric of optical absorption and the performance of quantum reservoir computers in terms of their short-term memory capacity. We establish this link by considering a coherent input encoding in conjunction with tunable qubit decay, giving precise control over the fading memory in the quantum reservoir computer. Our analysis enables us to identify a sweet-spot regime for the dissipation strength at which memory performance is maximized.

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Niclas Götting, Steffen Wilksen, Alexander Steinhoff, Frederik Lohof, Christopher Gies. 2025-01-26. Connection between memory performance and optical absorption in quantum reservoir computing. https://doi.org/10.1103/vp79-8t1l

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