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arXiv · 1304.5071

Off-equilibrium Langevin dynamics of the discrete nonlinear Schroedinger chain

S. Iubini·S. Lepri·R. Livi·A. Politi
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Abstract

Suitable Langevin thermostats are introduced which are able to control both the temperature and the chemical potential of a one-dimensional lattice of nonlinear Schrödinger oscillators. The resulting non-equilibrium stationary states are then investigated in two limit cases (low temperatures and large particle densities), where the dynamics can be mapped onto that of a coupled-rotor chain with an external torque. As a result, an effective kinetic definition of temperature can be introduced and compared with the general microcanonical (global) definition.

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S. Iubini, S. Lepri, R. Livi, A. Politi. 2013-08-21. Off-equilibrium Langevin dynamics of the discrete nonlinear Schroedinger chain. https://doi.org/10.1088/1742-5468%2F2013%2F08%2Fp08017

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