Paper detail

Asymmetric environment induces protein-like relaxation in spin chain

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.