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Hole-doped antiferromagnetic La2CoO4 has been known to possess intriguing electronic and magnetic phases due to the complex temperature and magnetic field dependent behavior of Co3+ ions. Here, we report on magnetic and dielectric observations in the half hole-doped La1.5Sr0.5CoO4. A Griffiths-like phase has been observed in the high temperature region below TG (∼244 K). At low temperature (∼55 K), a metamagnetic phase has been observed where antiferromagnetic correlations appear. On further cooling, a static weak antiferromagnetic ordering appears at ∼30 K, and a charge-spin glass state has been realized at ∼14 K.Hole-doped antiferromagnetic La2CoO4 has been known to possess intriguing electronic and magnetic phases due to the complex temperature and magnetic field dependent behavior of Co3+ ions. Here, we report on magnetic and dielectric observations in the half hole-doped La1.5Sr0.5CoO4. A Griffiths-like phase has been observed in the high temperature region below TG (∼244 K). At low temperature (∼55 K), a metamagnetic phase has been observed where antiferromagnetic correlations appear. On further cooling, a static weak antiferromagnetic ordering appears at ∼30 K, and a charge-spin glass state has been realized at ∼14 K.

The tailoring and understanding of the metal-insulator transitions (MITs) in vanadium sesquioxide, V2O3, is of major interest for both applications and fundamental physics. V2O3 has been characterized by MIT and concurrent structural transition at ∼155 K; however, the nature of the MIT has remained more elusive. We investigated the MIT and the electronic structure (in metallic phase) of the pulsed laser deposition grown strained vanadium sesquioxide thin films on Si. The strained thin films synthesized here show the suppression (by ∼23 K) of the MIT to lower temperatures, whilst the structural transition temperature decreases only by ∼10 K. Our results systematically confirm that albeit the structural changes are crucial in V2O3, electronic transition seems to be of Mott-Hubbard type. Stabilization of the metallic phase in the strained V2O3 thin film has been manifested from resistivity data and observations of the increased crystal field and quasiparticle features.