Structural localization in the Classical and Quantum Fermi-Pasta-Ulam Model

Abstract: We study the statistics and short-times dynamics of the classical and the quantum Fermi-Pasta-Ulam chain in thermal equilibrium. We analyze the distributions of single-particle configurations by integrating out the rest of the system. At low temperatures we observe a systematic increase in the mobility of the chain when transitioning from classical to quantum mechanics due to zero-point energy effects. We analyze the consequences of the quantum dispersion on the dynamics at short times of configurational correlation functions.