Advancements in Surface Plasmon Excitation through Surface Spin Waves

Recent research by H. Y. Yuan and Yaroslav Blanter has made significant strides in the field of surface plasmons, particularly in overcoming challenges associated with their excitation in two-dimensional (2D) materials. The paper, titled "Breaking surface plasmon excitation constraint via surface spin waves," presents a method to effectively excite transverse-electric (TE) surface plasmons across a frequency range from gigahertz to terahertz. This is achieved through a hybrid structure that combines dielectric materials, 2D materials, and magnetic components.

The authors highlight that the traditional difficulty in exciting TE surface plasmons arises from the need to conserve both energy and momentum simultaneously in standard 2D materials. Their findings indicate that incorporating surface spin waves provides an additional degree of freedom for plasmon excitation, which significantly enhances the electric field within the 2D medium.

Utilizing commonly available magnetic materials such as yttrium iron garnet (YIG) and manganese difluoride (MnF2), the researchers demonstrate that the excitation of surface plasmons can be observed as a measurable dip in the reflection spectrum of the hybrid system. Furthermore, they note that both the position and depth of this dip can be controlled through electric gating on the 2D layer and by applying an external magnetic field.

This advancement is poised to bridge the fields of low-dimensional physics, plasmonics, and spintronics, potentially leading to new integrations of plasmonic and spintronic devices. The implications of this research could extend to various applications, including enhanced light-matter interactions and the development of more efficient electronic and photonic devices.