A breakthrough in quantum physics is shedding new light on the complex phenomenon of many-body dynamical localization. Scientists have long debated whether interactions disrupt this effect in quantum systems, but a new study provides strong evidence that localization can persist even in the presence of multiple interacting particles.
Researchers introduced an extended mapping of the kicked Lieb-Liniger model, revealing two striking properties: on-site pseudorandomness and rapidly decaying couplings in the center-of-mass momentum. This discovery is crucial because it suggests that even in systems with finite interactions, localization doesn’t break down—it simply takes on a new form, governed by algebraic decay. The long-range coupling between relative momenta follows a distinct pattern, with a crossover in decay exponent as interactions strengthen.
This study isn’t just a theoretical exercise. By analyzing fractal dimensions and level-spacing ratios, scientists found strong signatures of near-integrability and multifractality—suggesting that quantum systems can exhibit complex, stable structures even under interaction. The findings provide a much-needed explanation for why strongly correlated quantum gases maintain their localized states, a phenomenon that has puzzled physicists for years.
To understand why this matters, consider Anderson’s localization theory, which showed that disorder in a system could completely halt particle transport. Instead of moving freely, a particle’s wave function becomes exponentially confined to a small region. The new research builds on this concept, showing that interactions don’t necessarily destroy localization but instead reshape it in a predictable way. This is a major leap in understanding how quantum particles behave in chaotic environments.
The kicked rotator model, often used to explore the transition from order to chaos, plays a key role in this breakthrough. Under certain conditions, this system behaves in an integrable manner, preserving its momentum over time. The study suggests that many-body dynamical localization may be a more universal phenomenon than previously thought, extending beyond simple models and into real-world quantum gases.
The implications of this work stretch far beyond theoretical physics. By deepening our understanding of localization, researchers are laying the groundwork for advances in quantum computing and condensed matter physics. Systems once thought to be too chaotic for stable quantum operations might, in fact, harbor hidden structures that can be harnessed for new technologies.
This discovery isn’t just another academic puzzle piece—it’s a glimpse into the underlying order of the quantum world. Localization, rather than being fragile, may be an inherent property of many-body quantum systems.
Sources:
https://verga.cpt.univ-mrs.fr/pages/kicked-localization.html
https://en.wikipedia.org/wiki/Kicked_rotator
https://physics.stackexchange.com/questions/409221/what-is-quantum-gas