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arXiv · 2505.15449

Controlling quantum phases with electric fields in one-dimensional Hubbard systems

D. Arisa·R. M. Dos Santos·Isaac M. Carvalho·Vivian V. França
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Abstract

Quantum systems under electric fields provide a powerful framework for uncovering and controlling novel quantum phases, especially in low-dimensional systems with strong correlations. In this work, we investigate quantum phase transitions induced by an electric potential difference in a one-dimensional half-filled Hubbard chain. By analyzing (i) tunneling and pairing mechanisms, (ii) charge and spin gaps, and (iii) entanglement between the chain halves, we identify three distinct phases: Mott insulator, metal and band-like insulator. The metallic regime, characterized by the closing of both charge and spin gaps, is accompanied by a field-dependent kinetic energy and a quasi-periodic oscillatory behavior of pairing response and entanglement. Although the metallic phase persists for different magnetizations, its extent in the phase diagram shrinks as spin polarization increases.

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D. Arisa, R. M. Dos Santos, Isaac M. Carvalho, Vivian V. França. 2025-05-21. Controlling quantum phases with electric fields in one-dimensional Hubbard systems. https://arxiv.org/abs/2505.15449

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