Anomalous non-additive dispersion interactions in systems of three one-dimensional wires

TL;DR

This study investigates the non-additive dispersion interactions among three one-dimensional wires, revealing a stronger effect and a different decay behavior than traditional models predict, with implications for understanding dispersion in low-dimensional systems.

Contribution

The paper demonstrates that non-additive dispersion interactions in 1D wires are significantly enhanced and follow a different power-law decay than classical triple-dipole models, providing new insights into dispersion in 1D systems.

Findings

Non-additive dispersion is significantly enhanced compared to triple-dipole predictions.

The decay follows a power law with exponents between 2.4 and 2.9, slower than the expected d^{-7}.

The results agree with charge-flow contribution estimates, indicating a different underlying mechanism.

Abstract

The non-additive dispersion contribution to the binding energy of three one-dimensional (1D) wires is investigated using wires modelled by (i) chains of hydrogen atoms and (ii) homogeneous electron gases. We demonstrate that the non-additive dispersion contribution to the binding energy is significantly enhanced compared with that expected from Axilrod-Teller-Muto-type triple-dipole summations and follows a different power-law decay with separation. The triwire non-additive dispersion for 1D electron gases scales according to the power law $d^{-\beta}$, where $d$ is the wire separation, with exponents $\beta(r_s)$ smaller than 3 and slightly increasing with $r_s$ from 2.4 at $r_s = 1$ to 2.9 at $r_s=10$, where $r_s$ is the density parameter of the 1D electron gas. This is in good agreement with the exponent $\beta=3$ suggested by the leading-order charge-flow contribution to the triwire non-additivity, and is a significantly slower decay than the $\sim d^{-7}$ behaviour that would be expected from triple-dipole summations.