  We investigate the entanglement properties in semiconductor quantum dot
systems modeled by extended Hubbard model, focusing on the impact of potential
energy variations and electron interactions within a four-site quantum dot spin
chain. Our study explores local and pairwise entanglement across configurations
with electron counts N=4 and N=6, under different potential energy settings. By
adjusting the potential energy in specific dots and examining the entanglement
across various interaction regimes, we identify significant variations in the
ground states of quantum dots. Our results reveal that local potential
modifications lead to notable redistributions of electron configurations,
significantly affecting the entanglement properties. These changes are depicted
in phase diagrams that show entanglement dependencies on interaction strengths
and potential energy adjustments, highlighting complex entanglement dynamics
and phase transitions triggered by inter-dot interactions.
