Quantum Many-Body Scars

Fri, Apr 19, 2019, 3:00 pm
B205 Engineering Quadrangle
Prof. Ravin Bhatt and Prof. Jeff Thompson


Recent experiments on large chains of Rydberg atoms [H. Bernien et al., Nature 551, 579 (2017)] have demonstrated the possibility of realizing 1D systems with locally constrained Hilbert spaces, along with some surprising signatures of non-ergodic dynamics, such as persistent oscillations following a quench from the Neel product state. In this talk I will argue that this phenomenon is a manifestation of a "quantum many-body scar", i.e., a concentration of extensively many eigenstates of the system around special many-body states [1]. The special states are analogs of unstable classical periodic orbits in the single-particle quantum billiards. I will present a model based on a single particle hopping on the Hilbert space graph, which quantitatively captures the scarred wave functions up to large systems of 32 atoms. These results suggest that scarred many-body bands give rise to a new universality class of quantum dynamics, which opens up opportunities for creating and manipulating novel states with long-lived coherence in systems that are now amenable to experimental study.

[1] C. J. Turner, A. A. Michailidis, D. A. Abanin, M. Serbyn and Z. Papić, Nature Phys, 14, 745 (2018).



Zlatko Papic is a Lecturer (i.e. Assistant Professor) in the Theoretical Physics Group at University of Leeds, United Kingdom. He obtained his PhD at Université Paris Sud in 2010. He was a postdoctoral researcher with Ravin Bhatt and Duncan Haldane at Princeton University (2010-2013), and a joint postdoctoral fellow between Perimeter Institute and Institute for Quantum Computing in Waterloo (2013-2015). His research spans condensed matter theory and quantum information, in particular quantum many-body physics, topological phases of matter, fractional quantum Hall effect, graphene, many-body localization and non-equilibrium quantum dynamics.

This seminar is supported with funds from the Korhammer Lecture Series