Abstract
Steady nonequilibrium states are investigated in a one-dimensional setup in the presence of two thermodynamic currents. Two paradigmatic nonlinear oscillators models are investigated: an XYchain and the discrete nonlinear Schrödinger equation. Their distinctive feature is that the relevant variable is an angle in both cases. We point out the importance of clearly distinguishing between energy and heat flux. In fact, even in the presence of a vanishing Seebeck coefficient, a coupling between (angular) momentum and energy arises, mediated by the unavoidable presence of a coherent energy flux. Such a contribution is the result of the ‘advection’ induced by the position-dependent angular velocity. As a result, in the XY model, the knowledge of the two diagonal elements of the
Onsager matrix suffices to reconstruct its transport properties. The analysis of the nonequilibrium steady states finally allows to strengthen the connection between the two models.
Onsager matrix suffices to reconstruct its transport properties. The analysis of the nonequilibrium steady states finally allows to strengthen the connection between the two models.
Original language | English |
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Article number | 083023 |
Pages (from-to) | 1-11 |
Number of pages | 11 |
Journal | New Journal of Physics |
Volume | 18 |
DOIs | |
Publication status | Published - 3 Aug 2016 |
Bibliographical note
AcknowledgementOne of us (AP) wishes to acknowledge S. Flach for enlightening discussions about the relationship between the DNLS equation and the rotor model.
Keywords
- transport processes
- heat transfer (theory)
- nonlinear oscillators
- XY model
- discrete nonlinear Schrdinger equation