Landau–Zener spin transitions in Fe2+–Fe2+ quantum dots controlling dislocation mobility in NaCl:Fe crystals
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Magnetic field induces transition in the distorted Fe2+–Fe2+ pairs (quantum dots) from the initial bonding singlet state to the high spin antibonding state providing decay of the pairs for two separated Fe2+ ions. Dislocations moving under internal stresses easily overcome separated Fe2+ ions in comparison with Fe2+–Fe2+ pairs lying close to the glide plane. Non-monotonous field dependence of dislocation displacements under internal stresses governed by short (100 μs) impulse of high magnetic fields up to 31 T was revealed in NaCl:Fe crystals. This non-typical dependence is the fingerprint of the Landau–Zener non-adiabatic spin transition between singlet and high spin states in quantum dots distorted by mechanical stresses of moving dislocations.
KeywordsEdge Dislocation High Spin State Ionic Crystal Dislocation Core Contact Pair
Authors thanks Russian Fund for Basic Researches (Grant no 13-07-12027) for financial support.
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