Ultra-fast Double Pulse All-Optical Re-switching of a Ferrimagnet

Abstract

All-optical re-switching has been investigated in the half-metallic Heusler ferrimagnet Mn2Ru0.9Ga, where Mn atoms occupy two inequivalent sites in the XA-type structure. The effect of a second 200 fs 800 nm pump pulse that follows a first pulse, when both are above the threshold for switching, is studied as a function of t12, the time between them. The aims are to identify the physical mechanisms involved and to determine the minimum time needed for re-switching. The time trajectory of the switching process on a plot of sublattice angular momentum, S4a vs S4c, is in three stages; When t < 0.1 ps, the sublattice moments are rapidly disordered, but not destroyed, while conserving net angular momentum via optical spin-wave excitations. This leads to transient parallel alignment of the residual Mn spins in the first quadrant. The net angular momentum associated with the majority sublattice then flips in about 2 ps, and a fully-reversed ferrimagnetic state is then established via the spin-lattice interaction, which allows re-switching provided t12 > 10 ps.

13 pages - 4 figures

References in corpus (10)

• All-optical control of ferromagnetic thin films and nanostructures
• Ultrafast photo-magnetic recording in transparent medium
• Single pulse all-optical toggle switching of magnetization without Gd: The example of Mn2RuxGa
• Two magnon bound state causes ultrafast thermally induced magnetisation switching
• Noninteger-spin magnonic excitations in untextured magnets
• Magnetocrystalline anisotropy and exchange probed by high-field anomalous Hall effect in fully-compensated half-metallic Mn2RuxGa thin films
• Magneto-optic Kerr effect in a spin-polarized zero-moment ferrimagnet
• Sub-picosecond exchange-relaxation in the compensated ferrimagnet Mn${}_2$Ru${}_x$Ga
• Giant spin-orbit torque in a single ferrimagnetic metal layer
• Magnetic reversal and pinning in a perpendicular zero moment half-metal

Cited by in corpus (10)

• Helicity-independent all-optical switching of magnetization in ferrimagnetic alloys
• Magnetic order and magneto-transport in half-metallic ferrimagnetic Mn${}_y$Ru${}_x$Ga thin films
• Single-pulse all-optical switching in amorphous Dy${}_x$Co${}_{1-x}$ and Tb${}_x$Co${}_{1-x}$
• Wide-field magneto-optical microscope to access quantitative magnetization dynamics with femtosecond temporal and sub-micrometer spatial resolution
• Realistic micromagnetic description of all-optical ultrafast switching processes in ferrimagnetic alloys
• Atomistic spin model of single pulse toggle switching in Mn${}_2$Ru${}_x$Ga Heusler alloys
• Analysis of ultrafast magnetization switching dynamics in exchange-coupled ferromagnet-ferrimagnet heterostructures
• Parametrically driven THz magnon-pairs: predictions towards ultimately fast and minimally dissipative switching
• First-principles insights into all-optical spin switching in the half-metallic Heusler ferrimagnet Mn${}_2$RuGa
• Single-Shot Magnetization Reversal in Ferromagnetic Spin Valves Enabled via Heat Control