Ultrafast optical generation of antiferromagnetic meron-antimeron pairs with conservation of topological charge

Abstract

We propose a new mechanism to produce a meron-antimeron pair in a two dimensional antiferromagnet with an ultrafast laser pulse via thermal Schwinger mechanism. Unlike ultrafast skyrmion nucleation, this process conserves total topological charge. We systematically show different stages of the dynamics and define proper topological invariants to characterise the configurations. The emergent structure can retain its topological structure for up to 100 ps. By introducing a topological structure factor we show that pair formation is robust against any random choice of initial magnetic configuration and can survive against disorder. Our findings demonstrate that the rich world of spin textures, which goes beyond conventional skyrmions, can be reached optically.

6 pages, 4 figures

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Cited by in corpus (6)

• Homochiral antiferromagnetic merons, antimerons and bimerons realized in synthetic antiferromagnets
• Skyrmion Generation through the Chirality Interplay of Light and Magnetism
• Poincaré sphere engineering of dynamical ferroelectric topological solitons
• Quantum Magnetic Skyrmions on Kondo-type Lattices
• Microscopic theory of current-induced skyrmion transport and its application in disordered spin textures
• Microscopic origin of scalar potential induced topological transition in massive Dirac fermions and scalar Hall effect