Disorder effects in the S=1 antiferromagnetic spin ladder CaV2O4
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Abstract
Abstract We study the physical properties of the antiferromagnetic spin ladder CaV 2 O 4 (CVO) and the Y-doped related compound Ca 0.9 Y 0.1 V 2 O 4 . In the latter, X-ray diffraction demonstrates the segregation of a small amount of a vanadium–perovskite impurity phase, leading to the formation of V vacancies within the main CVO-type structure. The 1D character of this calcium–vanadite enhances the influence of the vacancies on the electric and magnetic properties of Ca 0.9 Y 0.1 V 2 O 4 . Electrical transport is characterized by a variable-range hopping mechanism determined by the charging energy of nm-sized segments of V chains delimited by V vacancies, i.e. a Coulomb gap is formed at the Fermi level. These vacancies also locally affect the magnetic correlations, breaking the long-range AFM order observed in CaV 2 O 4 and producing exchange bias when the Y-doped sample is cooled with an applied magnetic field.
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Research context
OpenAlex topics: Advanced Condensed Matter Physics · Physics of Superconductivity and Magnetism · Magnetic and transport properties of perovskites and related materials
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References (31)
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