Tunable quantum criticality in multi-component Rydberg arrays

Abstract

Arrays of Rydberg atoms have appeared as a remarkably rich playground to study quantum phase transitions in one dimension. One of the biggest puzzles that was brought forward in this context is a commensurate-incommensurate phase transitions out of density waves. Experiments report the transitions with dynamical critical exponent $z>1$ that recent theoretical and numerical analysis attribute to the appearance of chiral transitions introduced by Huse and Fisher. However, further experimental exploration of these exotic transitions is complicated by the narrow parameter window where chiral transition can be realized. We argue that multi-component Rydberg arrays offer extra experimentally controllable parameters and provide a mechanism to tune quantum critical properties of the conformal Ashkin-Teller point that in turns controls the extent of the chiral transition. Here we consider an effective blockade model of two component Rydberg atoms - weak and strong components obeying nearest- and next-nearest-neighbor blockades. When laser detuning is applied to either strong or weak components the system is in the period-3 or period-2 phases correspondingly. However, laser detuning used for both components simultaneously stabilizes the period-4 phase partly surrounded by the chiral transition. We show that the extent of the chiral transition and even its appearance can be controlled by the relative ratio of the Rabi frequencies of the two components.Comment: 9 pages, 10 figure