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arXiv · 2601.05140

Enhanced Electron Reflectionat Mott-Insulator Interfaces

Jan Verlage·Peter Kratzer
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Abstract

The Klein paradox describes an incoming electron being scattered at a supercritical barrier to create electron-positron pairs, a phenomenon widely discussed in textbooks. While demonstrating this phenomenon experimentally with the fundamental particles remains challenging, condensed matter analogs are more accessible to experimental realization. For spinless quasi-particles, theoretical works show an enhancement of the pair production rate, and analogs of this effect in condensed matter systems have been studied theoretically. Here, we present another condensed matter system, a heterostructure comprised of two materials with strongly and weakly interacting electrons, that allows for constructing analytical solutions using the hierarchy-of-correlations method. The results show enhanced electron reflection related with the production of doublon-holon pairs, as known from the Klein paradox.

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Jan Verlage, Peter Kratzer. 2026-01-08. Enhanced Electron Reflectionat Mott-Insulator Interfaces. https://arxiv.org/abs/2601.05140

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