  We investigate the real-time current response of strongly-correlated quantum
dot systems under sinusoidal driving voltages. By means of an accurate
hierarchical equations of motion approach, we demonstrate the presence of
prominent memory effects induced by the Kondo resonance on the real-time
current response. These memory effects appear as distinctive hysteresis line
shapes and self-crossing features in the dynamic current-voltage
characteristics, with concomitant excitation of odd-number overtones. They
emerge as a cooperative effect of quantum coherence - due to inductive behavior
- and electron correlations - due to the Kondo resonance. We also show the
suppression of memory effects and the transition to classical behavior as a
function of temperature. All these phenomena can be observed in experiments and
may lead to novel quantum memory applications.
