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Register a new userCorrelating Quasi-Electron Relaxation with Quantum Femtosecond Magnetism in the Order Parameter Dynamics of Insulating Manganites
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Femtosecond (fs)-resolved simultaneous measurements of charge and spin dynamics reveal the coexistence of two different quasi-particle excitations in colossal magneto-resistive (CMR) manganites, with {em fs} and {em ps} relaxation times respectively. Their populations reverse size above a {em photoexcitation-intensity-threshold} coinciding with a sudden antiferro-to-ferromagnetic switching during $<$100 fs laser pulses. We present evidence that fast, metallic, mobile quasi--electrons dressed by {em quantum spin fluctuations} coexist with slow, localized, polaronic charge carriers in non-equilibrium phases. This may be central to CMR transition and leads to a laser-driven charge reorganization simultaneously with quantum fs magnetism via an emergent quantum-spin/charge/lattice transient coupling.
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