Title: Non-equilibrium Dynamics of Synthetic Quantum Matter

Speaker: Prof. Sayan Choudhury, HRI, Allahabad

Abstract: In recent years, rapid advances in the development of quantum technologies have led to the possibility of creating and manipulating large-scale “synthetic quantum matter”. These unique many-body platforms synthesized from ultracold atoms, molecules, ions, and photons provide a powerful and versatile route to elucidate quantum phenomena that may be difficult (or even impossible) to realize elsewhere in nature. In this talk, I will present some of our recent work on understanding the non-equilibrium dynamics of these systems. In the first part of the talk, I will demonstrate that geometrically frustrated spin chains can host localized many-body eigenstates in the absence of disorder. This localization arises from an interaction induced quantum interference, and it can persist even when the many-body spectrum is thermalizing. I will highlight the qualitative differences between our model and models of many-body localization. In the second part of the talk, I will describe quantum information scrambling in a non-integrable spin chain composed of two ingredients - a nearest-neighbor Ising coupling, and an infinite-range XX interaction. I will argue that this model can exhibit fast scrambling, even though it is not known to be holographically dual to a black hole. I will then briefly describe the kaleidoscope of quantum phases that emerge in this system and conclude with a proposal to realize this model in near-term experiments.