Eur. Phys. J. B 1, 223-227 (1998)
https://doi.org/10.1007/s100510050175

Level curvatures, spectral statistics and scaling for interacting particles

¹ Department of Physics, Technion, Israel Institute of Technology, 32000 Haifa, Israel
² CEA, Service de Physique de l'État Condensé, Centre d'Études de Saclay, 91191 Gif-sur-Yvette Cedex, France

Corresponding author: ^a eric@physics.technion.ac.il

Received: 26 September 1997
Accepted: 30 October 1997
Published online: 15 January 1998

Abstract

The mobility of two interacting particles in a random potential is studied, using the sensitivity of their levels to a change of boundary conditions. The delocalization in Hilbert space induced by the interaction of the two particle Fock states is shown to decrease the mobility in metals and to increase it in insulators. In contrast to the single particle case, the spectral rigidity is not directly related to the level curvature. Therefore, another curvature of topological origin is introduced, which defines the energy scale below which the spectrum has the universal Wigner-Dyson rigidity.