Informational non-equilibrium concentration- new paper published on Physical Review A

Today, our paper on informational non-equilibrium concentration is published on Physical Review A. Nice work Chung-Yun! It is my pleasure to collaborate with you and the Bristol Quantum Information Theory Group.

Informational contributions to thermodynamics can be studied in isolation by considering systems with fully degenerate Hamiltonians. In this regime, being in nonequilibrium (termed informational nonequilibrium) provides thermodynamic resources, such as extractable work, solely from the information content. The usefulness of informational nonequilibrium creates an incentive to obtain more of it, motivating the question of how to concentrate it: can we increase the local informational nonequilibrium of a product state under a global closed system (unitary) evolution? We fully solve this problem analytically, showing that it is impossible for two-qubits, and it is always possible to find states achieving this in higher dimensions. Specifically for two-qutrits, we find that there is a single unitary achieving optimal concentration for every state, for which we uncover a Mpemba-like effect. We further discuss the notion of bound resources in this framework, initial global correlations’ ability to activate concentration, and applications to concentrating purity and intrinsic randomness.