Enhanced Electron Reflection at Mott‐Insulator Interfaces

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, another condensed matter system, a heterostructure comprised of two materials with strongly and weakly interacting electrons is presented, 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.