Work

Interplay of Rashba spin-orbit coupling and Coulomb interaction in topological spin-triplet excitonic condensates

Year: 2026

Type: article

Abstract: The cooperative effect of Rashba spin-orbit coupling (SOC) and Coulomb attraction in stabilizing topological spin-triplet excitonic condensates (ECs) in two-dimensional electron-hole systems in external magnetic field is investigated by using an unrestricted Hartree-Fock approach combined with the random-phase approximation. At weak electron-hole Coulomb interaction, the intraband Rashba SOC induces spin-momentum locking and topological semimetal behavior, while stronger interaction stabilizes spin-triplet ECs. Increasing the valence-band SOC drives a transition from a topologically trivial EC with coexisting spin-up and spin-down components to a topological spin-up EC only with quantized Chern number $C=2$. The dynamical excitonic susceptibility reveals a soft spin-up triplet mode acting as the precursor of the condensate. These results establish a microscopic mechanism for Rashba SOC-induced topological ECs and suggest realistic situations for their realization in noncentrosymmetric Janus transition-metal dichalcogenides and twisted van der Waals heterostructures.

Source: Physical review. B./Physical review. B

DOI: 10.1103/bybf-jcmt

Authors: Quoc-Huy Ninh, Huu-Nha Nguyen, Van-Nham Phan

Institutions: Vietnam National University Ho Chi Minh City, Ho Chi Minh City University of Science, Duy Tan University

Language: English

Topic: Topological Materials and Phenomena

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funder: National Foundation for Science and Technology Development

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