Characterizing Many-Body Localization by Out-of-Time-Ordered Correlation

Understand

The out-of-time-ordered (OTO) correlation is a key quantity for quantifying quantum chaoticity and has been recently used in the investigation of quantum holography.

• Here we use it to study and characterize many-body localization (MBL).
• We find that a long-time logarithmic variation of the OTO correlation occurs in the MBL phase but is absent in the Anderson localized and ergodic phases.
• We extract a localization length in the MBL phase, which depends logarithmically on interaction and diverges at a critical interaction.