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Crossover from charge order to strain glass in phase separated manganite thin films: Impact of thermal cycling and substrate induced strain

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 نشر من قبل Vasudha Agarwal
 تاريخ النشر 2014
  مجال البحث فيزياء
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The magnetic and magnetotransport properties of single crystalline La1-x-yPryCaxMnO3 (x=0.42, y=0.40) thin films (~140 nm) deposited on (110) oriented LaAlO3 and SrTiO3 substrates exhibit a crossover from the high temperature antiferromagnetic-charge ordered insulator (AFM-COI) phase (T>TN) to strain glass (T<Tg). At intermediate temperatures (Tg<T<TN) dynamical liquid having prominent thermal-magneto-resistive hysteresis dominates in the cooling cycle, while in the warming cycle it is preceded by ferromagnetic metal (FMM) phase. Magnetic field required to drive AFM-COI to FMM phase transition are higher than that for the strain glass. The magneto-electric nature and temperature span of the distinct magnetic regimes are sensitive to the thermal cycling and substrate induced strain.



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