Title: Double pulse all-optical coherent control of ultrafast spin-reorientation in antiferromagnetic rare-earth orthoferrite

Abstract: A pair of circularly polarized laser pulses of opposite helicities are shown to control the route of spin reorientation phase transition in rare-earth antiferromagnetic orthoferrite SmTbFeO$_3$. The route can be efficiently controlled by the delay between the pulses and the sample temperature. Simulations employing earlier published models of laserinduced spin dynamics in orthoferrites failed to reproduce the experimental results. It is suggested that the failure is due to neglected temperature dependence of the antiferromagnetic resonance damping in the material. Taking into account the experimentally deduced temperature dependence of the damping, we have been able to obtain a good agreement between the simulations and the experimental results.