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arXiv · 0909.0606

One-Dimensional Quantum Transport Affected by a Background Medium: Fluctuations versus Correlations

S. Ejima·H. Fehske
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Abstract

We analyze the spectral properties of a very general two-channel fermion-boson transport model in the insulating and metallic regimes, and the signatures of the metal-insulator quantum phase transition in between. To this end we determine the single particle spectral function related to angle-resolved photoemission spectroscopy, the momentum distribution function, the Drude weight and the optical response by means of a dynamical (pseudo-site) density-matrix renormalization group technique for the one-dimensional half-filled band case. We show how the interplay of correlations and fluctuations in the background medium controls the charge dynamics of the system, which is a fundamental problem in a great variety of advanced materials.

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S. Ejima, H. Fehske. 2009-09-03. One-Dimensional Quantum Transport Affected by a Background Medium: Fluctuations versus Correlations. https://doi.org/10.1103/physrevb.80.155101

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