@article{6575, abstract = {Motivated by recent experimental observations of coherent many-body revivals in a constrained Rydbergatom chain, we construct a weak quasilocal deformation of the Rydberg-blockaded Hamiltonian, whichmakes the revivals virtually perfect. Our analysis suggests the existence of an underlying nonintegrableHamiltonian which supports an emergent SU(2)-spin dynamics within a small subspace of the many-bodyHilbert space. We show that such perfect dynamics necessitates the existence of atypical, nonergodicenergy eigenstates—quantum many-body scars. Furthermore, using these insights, we construct a toymodel that hosts exact quantum many-body scars, providing an intuitive explanation of their origin. Ourresults offer specific routes to enhancing coherent many-body revivals and provide a step towardestablishing the stability of quantum many-body scars in the thermodynamic limit.}, author = {Choi, Soonwon and Turner, Christopher J. and Pichler, Hannes and Ho, Wen Wei and Michailidis, Alexios and Papić, Zlatko and Serbyn, Maksym and Lukin, Mikhail D. and Abanin, Dmitry A.}, issn = {10797114}, journal = {Physical Review Letters}, number = {22}, publisher = {American Physical Society}, title = {{Emergent SU(2) dynamics and perfect quantum many-body scars}}, doi = {10.1103/PhysRevLett.122.220603}, volume = {122}, year = {2019}, }