Sticky electrons: When repulsion turns into attraction

EurekAlert  November 10, 2020
A few years ago, researchers in Austria were able to clarify mathematically where the boundary lies between the area that follows the known rules and the area where unusual effects play an important role. An international team of researchers (Austria, USA – Georgetown University, Italy, Germany) with the help of complex calculations on supercomputers, has explained exactly what happens when this boundary is crossed: the repulsion between the electrons is suddenly counteracted by an additional attractive force that enables completely counterintuitive effects. By decomposing local and uniform susceptibilities of the Hubbard model via their spectral representations, they proved how entering the nonperturbative regime causes an enhancement of the charge response, ultimately responsible for the phase-separation instabilities close to the Mott metal-insulator transition. Their analysis opens a new route for understanding phase transitions in the nonperturbative regime…read more. TECHNICAL ARTICLE