Entanglement transitions and multifractality in monitored free-fermions with random long-range hopping

@misc{fan2026entanglement,
  title = {{Entanglement transitions and multifractality in monitored free-fermions with random long-range hopping}},
  author = {Bo Fan and Antonio M. García-García},
  howpublished = {arXiv},
  year = {2026},
  month = sep,
  doi = {10.48550/arxiv.2607.23871},
  eprint = {2607.23871},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2607.23871},
}

TY  - UNPB
TI  - Entanglement transitions and multifractality in monitored free-fermions with random long-range hopping
AU  - Bo Fan
AU  - Antonio M. García-García
PY  - 2026
DA  - 2026/09/08
PB  - arXiv
DO  - 10.48550/arxiv.2607.23871
UR  - https://arxiv.org/abs/2607.23871
AB  - We study the entanglement dynamics of a one-dimensional chain of monitored non-interacting complex fermions with random power-law hopping characterized by a decay exponent α. For α≲ 1, in stark contrast with the case of hopping to nearest neighbors, the scaling of the entanglement entropy (EE) of the steady state with system size L is faster than logarithmic for any monitoring or disorder strength and it tends towards a linear (volume-law) scaling for sufficiently small α≲ 1/2. For α> 3/2, the EE is in the area-law phase, namely, no scaling with L, for any monitoring strength. For 1 < α≲ 3/2, we identify an α-dependent measurement-induced phase transition (MIPT) at a critical value of the monitoring strength separating the mentioned area-law and sub-volume-law phases. At this critical point, the EE scales logarithmically with system size, and the density-density correlation function, closely related to the EE, exhibits multifractal features. These results highlight the importance of superdiffusive classical hopping in the entanglement dynamic of quantum many-body systems and also help differentiate its role with respect to conventional sources of entanglement such as genuine quantum non-locality.
ER  -