Airy distribution of the quenched spectral form factor in non-interacting fermions
Abstract
For chaotic many-body systems as well as the random energy model, the logarithm of the (scaled) spectral form factor (SFF) exhibits two robust properties at late times: (i) self-averaging and (ii) a reflected-Gumbel distribution. Here, we demonstrate that both properties break down for N non-interacting fermions on a lattice of size L with an incommensurate single-particle spectrum. We show that the logarithm of the SFF, upon rescaling by 1/√L, follows the Airy distribution, in stark contrast to the reflected-Gumbel law. Moreover, it is no longer self-averaging, as its mean and standard deviation are of the same order. While deviations from reflected-Gumbel statistics are generically expected for non-interacting systems, we find that an interacting integrable model exhibits reflected-Gumbel statistics at late times, mirroring the chaotic case and distinguishing it from non-interacting fermions.
Related
- Maximal Orbital Entanglement from Non-Interacting Fermions
- Strongly interacting fermions under imaginary rotation
- Symmetric mass generation of interacting chiral fermions on a one-dimensional lattice without fermion doubling
- The quadratic density response function for non-interacting fermions at arbitrary temperature
- New Developments in Diagrammatic Monte Carlo for Interacting Lattice Fermions: Efficient Algorithms and Applications
BibTeX
@misc{martin2026airy,
title = {{Airy distribution of the quenched spectral form factor in non-interacting fermions}},
author = {Oscar Martin and Satya N. Majumdar and Laura Foini},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.41393},
eprint = {2610.41393},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.41393},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Airy distribution of the quenched spectral form factor in non-interacting fermions
AU - Oscar Martin
AU - Satya N. Majumdar
AU - Laura Foini
PY - 2026
DA - 2026/10/30
PB - arXiv
DO - 10.48550/arxiv.2610.41393
UR - https://arxiv.org/abs/2610.41393
AB - For chaotic many-body systems as well as the random energy model, the logarithm of the (scaled) spectral form factor (SFF) exhibits two robust properties at late times: (i) self-averaging and (ii) a reflected-Gumbel distribution. Here, we demonstrate that both properties break down for N non-interacting fermions on a lattice of size L with an incommensurate single-particle spectrum. We show that the logarithm of the SFF, upon rescaling by 1/√L, follows the Airy distribution, in stark contrast to the reflected-Gumbel law. Moreover, it is no longer self-averaging, as its mean and standard deviation are of the same order. While deviations from reflected-Gumbel statistics are generically expected for non-interacting systems, we find that an interacting integrable model exhibits reflected-Gumbel statistics at late times, mirroring the chaotic case and distinguishing it from non-interacting fermions.
ER -