Laser-induced real-space topology control of spin wave resonances

Femtosecond laser excitation of materials that exhibit magnetic spin textures promises advanced magnetic control via the generation of ultrafast and non-equilibrium spin dynamics. We explore such possibilities in ferrimagnetic [Fe(0.35 nm)/Gd(0.40 nm)]$_{160}$ multilayers, which host a rich diversity of magnetic textures from stripe domains at low magnetic fields, a dense bubble/skyrmion lattice at intermediate fields, and a single domain state for high magnetic fields. Using femtosecond magneto-optics, we observe distinct coherent spin wave dynamics in response to a weak laser excitation allowing us to unambiguously identify the different magnetic spin textures. Moreover, employing strong laser excitation we show that we achieve versatile control of the coherent spin dynamics via non-equilibrium and ultrafast transformation of magnetic spin textures by both creating and annihilating bubbles/skyrmions. We corroborate our findings by micromagnetic simulations and by Lorentz transmission electron microscopy before and after laser exposure.Comment: 19 article pages, 12 supplementar

PowerCube: Design and Development of a 100 W Origami-Inspired Deployable Solar Array for NanoSatellites

The rapid growth of the capabilities of small satellites have sparked the need for high-power deployable solar arrays. PowerCube addresses this need by proposing a unique solution that can generate up to 100W from a 1U stowed volume. At the core of this design is an innovative origami-inspired architecture, combined with advanced dual-matrix composite materials, to achieve excellent packaging efficiency and self-deployment capabilities. This paper provides an overview of the design of the system and presents the key analyses and breadboarding activities that supported its development. The next milestones in the ESA-funded PowerCube project are discussed, focusing on its qualification campaign. The paper is concluded by an overview of the PowerSat IOD mission, which will demonstrate a high-power 3U satellite, powered by the PowerCube solar array