Directed Polymers with Complex Amplitudes

摘要

The generalized directed polymer model in which the amplitudes along a polymer assume random complex values is studied. It is shown that complex disorder can cause stronger transverse fluctuations than real positive disorder previously studied. A replica method is used to map the model onto a system of n pairs of opposite charged bosons. Quantitative analytical arguments are given to show that complex disorder results in larger transverse fluctuations.