The Mpemba effect — the counterintuitive phenomenon in which a hotter system can reach thermal equilibrium faster than a cooler one — has a well-understood classical explanation rooted in rugged energy landscapes. Translating this picture into quantum mechanics has proven difficult, largely because quantum coherence disrupts the classical intuition. A new preprint posted to arXiv proposes a concrete quantum mechanism using Stark localization, in which a linear potential gradient localizes particles in energy space, effectively engineering the kind of landscape needed to reproduce the effect.
The authors couple this engineered landscape to localized incoherent hopping driven by rare detection events — essentially, dissipative jumps whose rate scales with energy. Because higher-energy states trigger these cooling hops more frequently, they can shed energy faster than lower-energy states, producing what the authors describe as super-exponentially separated cooling timescales for localized initial states. The effect is further amplified, they argue, when attractive on-site interactions cause particles to hop collectively as bound pairs, dramatically enhancing the timescale separation.
This work is an unreviewed preprint and has not yet undergone peer review; its claims should be read accordingly. The authors assert that the predicted signatures are accessible in current experimental platforms, suggesting potential near-term tests. Whether the mechanism survives scrutiny as a robust and general route to the quantum Mpemba effect remains to be established.