Metamaterial analogue of Ising model

TL;DR

This paper presents a terahertz metamaterial that emulates 2D Ising model spin interactions through complex electromagnetic multipole interactions, enabling passive multispectral applications without external fields.

Contribution

It introduces a metamaterial platform that passively mimics microscopic spin interactions using Fano resonances, advancing the understanding of complex physical phenomena.

Findings

Observation of Fano resonances due to strong nearest-neighbor interactions

Manipulation of 2D interactions without external magnetic or electric fields

Potential applications in super-resolution imaging and biosensing

Abstract

The interaction between microscopic particles has always been a fascinating and intriguing area of science. Direct interrogation of such interactions is often difficult or impossible. Structured electromagnetic systems offer a rich toolkit for mimicking and reproducing the key dynamics that governs the microscopic interactions, and thus provide an avenue to explore and interpret the microscopic phenomena. In particular, metamaterials offer the freedom to artificially tailor light-matter coupling and to control the interaction between unit cells in the metamaterial array. Here we demonstrate a terahertz metamaterial that mimics spin-related interactions of microscopic particles in a 2D lattice via complex electromagnetic multipole interactions within the metamaterial array. Fano resonances featured by distinct mode properties due to strong nearest-neighbor interactions are discussed that draw parallels with the 2D Ising model. Interestingly, a hyperfine Fano splitting spectrum is observed by manipulating the 2D interactions without applying external magnetic or electric fields, which provides a passive multispectral platform for applications in super-resolution imaging, biosensing, and selective thermal emission. The dynamic approach to reproduce the static interaction between microscopic particles would enable more profound significance in exploring the unknown physical world by the macroscopic analogues.