Work

Exploring Entanglement Spectra and Phase Diagrams in Multi-Electron Quantum Dot Chains

Year: 2025

Type: article

Abstract: We investigate the entanglement properties in semiconductor quantum dot systems modeled by the extended Hubbard model, focusing on the impacts 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. We extend this analysis to larger systems with L=6 and L=8, comparing electron counts N=L and N=L+2, revealing sharper entanglement transitions and reduced finite-size effects as the system size increases. Our results show that local potential shifts and the Coulomb interaction strength lead to notable redistributions of the electron configurations in the quantum dot spin chain, significantly affecting the entanglement properties. These changes are depicted in phase diagrams that highlight entanglements' dependencies on the interaction strengths and potential energy adjustments, illustrating complex entanglement dynamics shifts triggered by interdot interactions.

Source: Entropy

DOI: 10.3390/e27050479

Authors: Guanjie He, Xin Wang

Institutions: City University of Hong Kong, City University of Hong Kong, Shenzhen Research Institute, Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area

Language: English

Topic: Quantum and electron transport phenomena

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $3,137

Funders: National Natural Science Foundation of China, Shenzhen Fundamental Research Program