This paper reports on the observation of Kondo physics in a single-electron transistor (SET). The Kondo effect occurs when an unpaired electron interacts with delocalized electrons in a metal, forming a spin singlet state at low temperatures. The study shows that in a SET, a confined electron droplet behaves like an artificial atom, and the Kondo effect can be observed when the number of electrons on the artificial atom is odd, leading to an enhancement of zero-bias conductance. This effect is sensitive to voltage, magnetic field, and temperature, and is consistent with theoretical predictions. The SETs used in this study are fabricated using multiple metallic gates on a GaAs/AlGaAs heterostructure, creating a droplet of electrons separated from the leads by tunnel junctions. The droplet's size is critical for observing the Kondo effect, as smaller droplets allow for larger energy scales and thus more pronounced Kondo phenomena. The study measures the differential conductance as a function of gate voltage and drain-source voltage, revealing the periodic spacing of conductance peaks and the suppression of zero-bias conductance at high temperatures or large applied voltages. The Kondo effect is observed through the formation of a spin singlet between the localized electron and delocalized electrons, leading to an enhanced density of states at the Fermi level and thus increased conductance. This effect is suppressed by increasing temperature or applying a magnetic field, which splits the spin singlet into a Zeeman doublet. The study also shows that the Kondo resonance is sensitive to the difference in Fermi levels between the leads, and that the splitting of differential conductance peaks provides a distinctive signature of Kondo physics. The results demonstrate that the characteristics of the SET are strongly influenced by the coupling between the electron droplet and the leads. The study highlights the importance of the Kondo effect in understanding quantum transport in nanoscale devices and suggests that these devices may have technological relevance due to their potential for high-speed operation. The findings are consistent with theoretical predictions and provide new insights into the behavior of electrons in confined systems.This paper reports on the observation of Kondo physics in a single-electron transistor (SET). The Kondo effect occurs when an unpaired electron interacts with delocalized electrons in a metal, forming a spin singlet state at low temperatures. The study shows that in a SET, a confined electron droplet behaves like an artificial atom, and the Kondo effect can be observed when the number of electrons on the artificial atom is odd, leading to an enhancement of zero-bias conductance. This effect is sensitive to voltage, magnetic field, and temperature, and is consistent with theoretical predictions. The SETs used in this study are fabricated using multiple metallic gates on a GaAs/AlGaAs heterostructure, creating a droplet of electrons separated from the leads by tunnel junctions. The droplet's size is critical for observing the Kondo effect, as smaller droplets allow for larger energy scales and thus more pronounced Kondo phenomena. The study measures the differential conductance as a function of gate voltage and drain-source voltage, revealing the periodic spacing of conductance peaks and the suppression of zero-bias conductance at high temperatures or large applied voltages. The Kondo effect is observed through the formation of a spin singlet between the localized electron and delocalized electrons, leading to an enhanced density of states at the Fermi level and thus increased conductance. This effect is suppressed by increasing temperature or applying a magnetic field, which splits the spin singlet into a Zeeman doublet. The study also shows that the Kondo resonance is sensitive to the difference in Fermi levels between the leads, and that the splitting of differential conductance peaks provides a distinctive signature of Kondo physics. The results demonstrate that the characteristics of the SET are strongly influenced by the coupling between the electron droplet and the leads. The study highlights the importance of the Kondo effect in understanding quantum transport in nanoscale devices and suggests that these devices may have technological relevance due to their potential for high-speed operation. The findings are consistent with theoretical predictions and provide new insights into the behavior of electrons in confined systems.