Thermalisation is when an object becomes thermally equal to its surroundings so that it is in perfect thermal equilibrium. In this state the entropy of the system is at its maximum and it becomes impossible to return it to its original state without outside influence. This means on the quantum scale that all information is lost and generally all quantum systems reach this point sooner or later. There are some unique cases where this doesn’t happen and one of these is in many bodied localisation (MBL).
Localisation, often called Anderson localisation, is when waves do not diffuse through chaotic systems. This is true for acoustic, electromagnetic, quantum and any other kind of waves. In MBL the system doesn’t thermalise but remains at a set state above the background temperature. By generating these MBLs researchers have managed to experimentally observe systems that can remember their original quantum state as well as energy distributions and entanglement statistics for the system. Expansions on this research will create more detailed models of MBLs and develop more applications for these anti-entropy systems.