Negative differential conductivity in Heisenberg XXZ chain far from equilibrium

Tomaz Prosen

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arXiv · 0704.2252

Negative differential conductivity in Heisenberg XXZ chain far from equilibrium

Tomaz Prosen

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Abstract

Negative differential conductivity is reported for the far from equilibrium quantum spin transport in the insulating regime (J_x < J_z) of finite Heisenberg XXZ spin 1/2 chains. The phenomenon is reproduced analytically for small chains of N=4 spins and further analyzed numerically, for up to N=16, using an efficient pure-state simulation with stochastic spin baths.

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Tomaz Prosen. 2007-04-17. Negative differential conductivity in Heisenberg XXZ chain far from equilibrium. https://arxiv.org/abs/0704.2252

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