Low loss spin wave resonances in organic-based ferrimagnet vanadium tetracyanoethylene thin films

TL;DR

This paper reports high-quality spin wave resonances in organic ferrimagnet thin films, demonstrating their potential for magnonic devices with high Q-factors comparable to inorganic materials.

Contribution

It experimentally demonstrates high-Q spin wave resonances in organic ferrimagnet thin films and extracts key material parameters, showing their suitability for hybrid magnonic applications.

Findings

High quality factor (>3200) spin wave resonances observed at room temperature.

Exchange constant of V[TCNE]$_2$ measured as $(4.61\u00b1 0.35) imes 10^{-16} ext{m}^2$.

Organic ferrimagnet thin films can rival inorganic materials in magnonic performance.

Abstract

We experimentally demonstrate high quality factor spin wave resonances in an encapsulated thin film of the organic-based ferrimagnet vanadium tetracyanoethylene (V[TCNE]$_\textit{x~2}$) coated on an a-plane sapphire substrate by low temperature chemical vapor deposition. The thickness standing wave modes are observed in a broad frequency range (1 GHz ~ 5 GHz) with high quality factor exceeding 3,200 in ambient air at room temperature, rivaling those of inorganic magnetic materials. The exchange constant of V[TCNE]$_\textit{x~2}$, a crucial material parameter for future study and device design of the V[TCNE]$_\textit{x~2}$, is extracted from the measurement with a value of $(4.61\pm 0.35)\times 10^{-16} \mathrm{\: m^{2}}$. Our result establishes the feasibility of using organic-based materials for building hybrid magnonic devices and circuits.