Stability of many-body localization in Floquet systems

We study many-body localization (MBL) transition in disordered Floquet systems using a polynomially filtered exact diagonalization (POLFED) algorithm. We focus on disordered kicked Ising model and quantitatively demonstrate that finite-size effects at the MBL transition are less severe than in the random field XXZ spin chains widely studied in the context of MBL. Our conclusions extend also to other disordered Floquet models, indicating smaller finite-size effects than those observed in the usually considered disordered autonomous spin chains. We observe consistent signatures of the transition to MBL phase for several indicators of ergodicity breaking in the kicked Ising model. Moreover, we show that an assumption of a power-law divergence of the correlation length at the MBL transition yields a critical exponent nu approximate to 2, consistent with the Harris criterion for one-dimensional disordered systems.

Automated summary

We use a polynomially filtered exact diagonalization algorithm to study the many-body localization (MBL) transition in disordered Floquet systems. We focus on the disordered kicked Ising model and demonstrate quantitatively that finite-size effects at the MBL transition are less severe than in the random field XXZ spin chains commonly studied in the context of MBL. Our findings also apply to other disordered Floquet models, showing smaller finite-size effects than those observed in typical disordered autonomous spin chains. We observe consistent indications of the MBL transition for several indicators of ergodicity breaking in the kicked Ising model. Additionally, we find that assuming a power-law divergence of the correlation length at the MBL transition yields a critical exponent nu approximately equal to 2, in agreement with the Harris criterion for one-dimensional disordered systems.