Coherent forward scattering as a robust probe of multifractality in critical disordered media

• Published in: SciPost physics Vol. 14; no. 3; p. 057
• Main Authors: Martinez, Maxime, Lemarié, Gabriel, Georgeot, Bertrand, Miniatura, Christian, Giraud, Olivier
• Format: Journal Article
• Language: English
• Published: SciPost Foundation 01-03-2023; SciPost
• Subjects: Physics
• ISSN: 2542-4653; 2542-4653
• DOI: 10.21468/SciPostPhys.14.3.057

We study coherent forward scattering (CFS) in critical disordered systems, whose eigenstates are multifractals. We give general and simple arguments that make it possible to fully characterize the dynamics of the shape and height of the CFS peak. We show that the dynamics is governed by multifractal dimensions
D_1
D
1
and
D_2
D
2
, which suggests that CFS could be used as an experimental probe for quantum multifractality. Our predictions are universal and numerically verified in three paradigmatic models of quantum multifractality: Power-law Random Banded Matrices (PRBM), the Ruijsenaars-Schneider ensembles (RS), and the three-dimensional kicked-rotor (3DKR). In the strong multifractal regime, we show analytically that these universal predictions exactly coincide with results from standard perturbation theory applied to the PRBM and RS models.