Enhanced THz emission from spintronic Fe/Pt emitters through crystal growth optimization

TL;DR

This study demonstrates that optimizing crystal growth in epitaxial Fe/Pt heterostructures significantly enhances THz emission amplitude and bandwidth by reducing spin scattering and improving interface transmission, advancing spintronic THz emitter development.

Contribution

It reveals how crystal growth optimization of Fe layers improves THz emission and provides insights into spin current dynamics in metallic heterostructures.

Findings

Enhanced THz emission amplitude and bandwidth with optimized growth

Reduced spin scattering and improved interface transmission

Crystal growth optimization as a pathway for better spintronic THz emitters

Abstract

We investigate the THz emission characteristics of ferromagnetic/non-magnetic metallic heterostructures, focusing on thin Fe/Pt bilayers. In particular, we report on the impact of optimized crystal growth of the epitaxial Fe layers on the THz emission amplitude and spectral bandwidth. We demonstrate an enhancement of the emitted intensity along with an expansion of the emission bandwidth. Both are related to reduced spin scattering and higher interface transmission. Our work provides a pathway for devicing optimal spintronic THz emitters based on epitaxial Fe. It also highlights how THz emission measurements can be utilized to characterize the changes in out-of-equilibrium spin current dynamics in metallic heterostructures, driven by subtle structural refinement.