Patra, K Pushpanjali2024-02-052024-02-052024ROLL NO.186121011https://gyan.iitg.ac.in/handle/123456789/2540Supervisor: Ravi, SThe recent scientific focus on R2CoMnO6 (R is trivalent rare earth element) stems from its intriguingly complex magnetic behavior, which has opened up a diverse range of potential applications. Such as metamagnetic behavior, magneto-electric coupling, multiferroic behavior, spin-phonon coupling, magnetization reversal (MR) and tunable exchange bias behavior, magnetocaloric effect, low-temperature magnetic frustration and large magneto-resistance like properties. Few research groups have been started working on Ho2CoMnO6, and reported a FM TC around 77 K, with a large magnetic entropy (Sm) of value ~ 12 J/kg.K at a 7 T field. This feature makes this material applicable for magnetic refrigeration. R2FeCrO6 are also an important family of magnetic double perovskites, while Fe-Cr based perovskites have been extensively studied, there has been relatively limited exploration of Fe-Cr based double perovskites. Hence, our current research is centred on exploring the magnetic DP materials based on Co-Mn (Ho2CoMnO6) and Fe-Cr (Y2FeCrO6), with the primary objective of tuning and comprehending their magnetic properties in this direction. To the best of our understanding, there hasn't been much study done on nanostructured Ho2CoMnO6 and Y2FeCrO6 DPs, despite their high interest. In this work we have synthesizing nanostructured Ho2CoMnO6 and Y2FeCrO6 DPs and emphasis on the investigation of their structural and magnetic characteristics.enNanomagnetismDouble PerovskitesNegative MagnetizationExchangebias BehaviorSpin FrustrationThesis