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arXiv · 2608.13161

Controlled dynamics of a multi-component discrete-time quantum walker

Vikash Mittal·Tomasz Sowiński
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Abstract

We investigate a discrete-time quantum walk of a three-component quantum particle on a one-dimensional lattice. As coin operators, we employ parameterized rotations generated by the Gell-Mann matrices, which enable systematic tuning of the couplings between the internal components. We analyze how these couplings influence and control the dynamics by systematically exploring the position-space probability distribution across a broad region of the parameter space. To quantify the impact of different inter-component couplings, we further examine the ratio of the mean position to the variance in each half of the lattice. Our results indicates that the system supports a rich variety of transport regimes, ranging from nearly symmetric, rapidly spreading walks to strongly anisotropic dynamics with partial localization. This framework thus provides a new avenue for engineering targeted spreading and trapping behavior in multicomponent discrete-time quantum walks.

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Vikash Mittal, Tomasz Sowiński. 2026-08-13. Controlled dynamics of a multi-component discrete-time quantum walker. https://arxiv.org/abs/2608.13161

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