Glasses have the interesting feature of being neither integrable nor fully chaotic. They thermalize quickly within a subspace but thermalize much more slowly across the full space due to high free energy barriers which partition the configuration space into sectors. Past works have examined the Rosenzweig-Porter (RP) model as a minimal quantum model which transitions from localized to chaotic behavior. In this work we generalize the RP model in such a way that it becomes a minimal model which transitions from glassy to chaotic behavior, which we term the "Block Rosenzweig-Porter" (BRP) model. We calculate the spectral form factors of both models at all timescales larger than the inverse spectral width. Whereas the RP model exhibits a crossover from localized to ergodic behavior at the Thouless timescale, the new BRP model instead crosses over from glassy to fully chaotic behavior, as seen by a change in the steepness of the ramp of the spectral form factor.
Authors / Affiliations: mappings to Contributors and OrganizationsSee all Organizations.
- 1 Richard Barney,
- 1 Michael Winer,
- 1 Christopher L. Baldwin,
- 2 Brian Swingle,
- 1 3 Victor Galitski
- Advanced Scientific Computing Research
- Air Force Office of Scientific Research [AFOSR]
- Army Research Office (ARO) (through Organization: United States Army Research Laboratory [ARL])
- Defense Advanced Research Projects Agency
- Joint Quantum Institute
- National Science Foundation [NSF]
- Office of Science
- Simons Foundation
- United States Department of Energy [DOE]