Condensed Matter

Quantum many-body scars (QMBS) have emerged as a captivating anomaly within the landscape of quantum physics, challenging the conventional expectations of the eigenstate thermalization hypothesis (ETH). According to ETH, an isolated quantum system is expected to evolve toward thermal equilibrium, with local observables equilibrating to values predicted by statistical mechanics, independent of the initial state of the system. However, QMBS present a remarkable exception by exhibiting resistance to thermalization, thus maintaining quantum information for unexpectedly long durations.

This colloquium will delve into the intriguing realm of QMBS, highlighting their pivotal role in advancing our understanding of quantum thermalization and their potential applications in quantum dynamics and technology. The discussion will cover recent theoretical and experimental progress in identifying systems that display these scars, focusing on their properties and the mechanisms by which they arise.

A specific area of interest is the construction of QMBS states emerging from Einstein-Podolsky-Rosen (EPR) states in bilayer systems, where each layer is maximally entangled. We will explore applications of this framework in quantum dimer models, examining various features of the bilayer model that contribute to the emergence of these states. Furthermore, if time allows, the talk will extend to systems of itinerant bosons, demonstrating how an infinite tower of many-body scar states can manifest in bilayer Bose-Hubbard models with charge conservation. We will discuss the implications of these findings in the context of recent experimental advancements, considering how these theoretical constructs relate to physically realizable systems in laboratory settings.