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arXiv · 2501.18489

Dissipation in fermionic two-body continuous-time quantum walk under the steepest entropy ascent formalism

Rohit Kishan Ray·R. Srikanth·Sonjoy Majumder
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Abstract

Quantum walks play a crucial role in quantum algorithms and computational problems. Many-body quantum walks can reveal and exploit quantum correlations that are unavailable for single-walker cases. Studying quantum walks under noise and dissipation, particularly in multi-walker systems, has significant implications. In this context, we use a thermodynamically consistent formalism of dissipation modeling, namely the steepest entropy ascent (SEA) formalism. We analyze two spinless fermionic continuous-time walkers on a 1D graph with tunable Hubbard and extended Hubbard-like interactions. By contrasting SEA-driven dynamics with unitary evolution, we systematically investigate how interaction strengths modulate thermalization and entropy production. Our findings highlight the relevance of SEA formalism in modeling nonlinear dissipation in many-body quantum systems and its implications for quantum thermalization.

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Rohit Kishan Ray, R. Srikanth, Sonjoy Majumder. 2025-01-30. Dissipation in fermionic two-body continuous-time quantum walk under the steepest entropy ascent formalism. https://doi.org/10.1103/ftsw-cwbq

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