Strain-gradient-modulated Kondo effect at the LaAlO3/SrTiO3 heterointerface

Modulation of Kondo phenomenon in two-dimensional materials is of great significance. Unfortunately, the strain effect, one of the effective regulation methods, is usually lacking in previously studied Kondo systems. Here we show that a tensile or compressive strain gradient induced by a three-point bending apparatus has a prominent impact on Kondo effect of the two dimensional electron gas at the LaAlO3/SrTiO3 heterointerface. Under the tensile strain gradient, Kondo temperature (TK) decreases. In contrast, TK increases under the compressive strain gradient. At the same time, the temperature at which the resistance has a minimum, Tmin, shows the same strain gradient dependence as TK. The present study may pave the way for manipulating manybody effects at oxide heterointerface.

Automated summary

Modulating the Kondo phenomenon in two-dimensional materials is important. However, the strain effect, one of the effective regulation methods, is typically absent in previous studies of Kondo systems. In this study, we demonstrate that a tensile or compressive strain gradient induced by a three-point bending apparatus significantly impacts the Kondo effect of the two-dimensional electron gas at the LaAlO3/SrTiO3 heterointerface. Under the tensile strain gradient, the Kondo temperature (TK) decreases, while TK increases under the compressive strain gradient. Additionally, the temperature at which the resistance has a minimum, Tmin, exhibits the same strain gradient dependence as TK. This research may open doors for manipulating many-body effects at oxide heterointerfaces.