Entanglement transition of elastic lines in a strongly disordered environmentV. Petäjä1, M. Alava1, 2 and H. Rieger3
1 Helsinki University of Technology, Laboratory of Physics P.O. Box 1100, 02015 HUT, Finland
2 SMC-INFM, Dipartimento di Fisica, Università "La Sapienza" P.le A. Moro 2, 00185 Roma, Italy
3 Theoretische Physik, Universität des Saarlandes - 66041 Saarbrücken, Germany
(Received 8 December 2003; accepted in final form 11 April 2004)
We investigate by exact optimization the geometrical properties of three-dimensional elastic line systems with point disorder and hard-core repulsion. The line "forests" become entangled due to increasing line wandering as the system height is increased, at fixed line density. There is a transition height at which a cluster of pairwise entangled lines spans the system, transverse to average line orientation. Numerical evidence implies that the phenomenon is in the ordinary percolation universality class. Similar results are obtained for an ensemble of flux lines obeying random-walk dynamics.
05.40.-a - Fluctuation phenomena, random processes, noise, and Brownian motion.
74.25.Qt - Vortex lattices, flux pinning, flux creep.
74.62.Dh - Effects of crystal defects, doping and substitution.
© EDP Sciences 2004