Asymmetric environment induces protein-like relaxation in spin chain

TL;DR

This study demonstrates that asymmetric environmental interactions can induce protein-like relaxation behaviors in open spin chains, highlighting the importance of system-environment coupling in complex relaxation dynamics.

Contribution

It reveals that environmental asymmetry alone can produce protein-like relaxation in spin chains, extending understanding beyond traditional frustration-based models.

Findings

Asymmetric baths block energy minimization in spin chains.

Environmental asymmetry induces excitation resembling protein denaturation.

Protein-like relaxation emerges without energetic frustration.

Abstract

Proteins are aminoacid chains that diffusively fold or unfold depending on the thermal and chemical environmental conditions. While sophisticated models account for detailed aspects of real proteins, finding traits that unify protein dynamics to general open chains relaxation is still challenging. The principle of minimal frustration represents a key step towards this goal, revealing a fundamental link between proteins and spin glasses. Here, we search for the emergence of protein-like relaxation in open spin chains by going beyond the validity domain of the minimal frustration principle as to focus on the role of system-environment interactions rather than on frustration in the system's Hamiltonian. We find that strong asymmetries between the couplings of each spin to its immediate surroundings imply close similarities to protein folding and unfolding dynamics. Namely, an asymmetric bath can (i) block the system from finding its minimum energy state, even in the complete absence of energetic frustration in the system's Hamiltonian, and (ii) excite the system resembling the well-known distinction between thermal and chemical denaturations.