Accessing ultrafast spin-transport dynamics in copper using broadband terahertz spectroscopy

Abstract

We study the spatiotemporal dynamics of ultrafast electron spin transport across nanometer-thick copper layers using broadband terahertz spectroscopy. Our analysis of temporal delays, broadening and attenuation of the spin-current pulse revealed ballistic-like propagation of the pulse peak, approaching the Fermi velocity, and diffusive features including a significant velocity dispersion. A comparison to the frequency-dependent Ficks law identified the diffusion-dominated transport regime for distances larger than 2 nm. The findings lie the groundwork for designing future broadband spintronic devices.

V3: AAM, Licence: CC BY Main text consists of 3 figures and 4 pages of text

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Cited by in corpus (3)

• Deciphering the origin of spin current in spintronic terahertz emitters and its imprint on their electromagnetic radiation via time-dependent density functional theory
• Optimizing spin-based terahertz emission from magnetic heterostructures
• Optically induced magnetic inertia and magnons from non-Markovian extension of the Landau-Lifshitz-Gilbert equation