Abstract
Using periodic-orbit theory beyond the diagonal approximation we investigate the form factor, , of a generic quantum graph with mixing classical dynamics and time-reversal symmetry. We calculate the contribution from pairs of self-intersecting orbits that differ from each other only in the orientation of a single loop. In the limit of large graphs, these pairs produce a contribution to the form factor which agrees with random-matrix theory.
- Received 10 August 2001
DOI:https://doi.org/10.1103/PhysRevLett.88.104101
©2002 American Physical Society