Among the perovskite oxide family, KTaO3 (KTO) has recently attracted considerable interest as a possible system for the realization of the Rashba effect. In this work, we improvise a novel conducting interface by juxtaposing KTO with another insulator, namely LaVO3 (LVO) and report planar Hall effect (PHE) and anisotropic magnetoresistance (AMR) measurements. This interface exhibits a signature of strong spin-orbit coupling. Our experimental observation of two fold AMR at low magnetic fields can be intuitively understood using a phenomenological theory for a Rashba spin-split system. At high fields (∼8 T), we see a two fold to four fold transition in the AMR that could not be explained using only Rashba spin-split energy spectra. We speculate that it might be generated through an intricate process arising from the interplay between strong spin-orbit coupling, broken inversion symmetery, relativistic conduction electron and possible uncompensated localized vanadium spins.

The momentum‐dependent splitting of spin‐bands in an electronic system is known as the “Rashba effect.” Systems with the Rashba effect possess a Dirac point in momentum space, which may act as a source of Berry's phase for the conduction electrons of such system. Herein, the Shubnikov–de Haas oscillations (SdH) at the conducting interface of EuO–KTaO3 (KTO) are reported. The observed SdH oscillations suggest the presence of two Fermi surfaces. For both Fermi surfaces, the presence of a Berry's phase is seen. Strong spin–orbit coupling is also observed in this system. The existence of two Fermi surfaces with Berry's phase along with the signature of strong spin–orbit coupling suggest the formation of Rashba spin‐split bands. As in topological insulators, two‐fold planar Hall effect and anisotropic magnetoresistance are also observed in EuO–KTO. Analyzing the SdH, Hall, and magnetoresistance data, the authors draw a possible band diagram near the Fermi surface.

Despite the promising role of magnetic hyperthermia in cancer therapy, its use in patients has been restricted by hurdles that include inefficient targeting of magnetic particles to the tumor site, limited bioavailability, and high toxicity, etc. Taking advantage of the unique metabolic property of cancer cells, we explored the potential of these cells to biosynthesize magnetic nanoparticles for potential hyperthermia applications. Treatment of cancer cells with a mixture of FeCl 2 and zinc gluconate resulted in a significant increase in intracellular Fe and Zn content in these cells. Exposure of these cells to an alternating magnetic field (AMF) for 30 min resulted in a substantial temperature rise of 5−6 °C. The in situ formed particles were identified as iron oxide and ZnO nanoparticles. Based on the magnetic property and size, the iron oxide nanoparticles were classified as superparamagnetic iron oxide nanoparticles (SPIONS) comprising a mixture of magnetite (Fe 3 -δO 4 ) and maghemite (γ-Fe 2 O 3 ). The role of reactive oxygen species (H 2 O 2 ) and the involvement of the glycolytic pathway in the biosynthesis of the nanoparticles were confirmed using appropriate in vitro studies. The simplicity of treatment, the specificity of cells capable of synthesis of SPIONS, and the hyperthermia response observed in cancer cells indicate a promising strategy to achieve effective magnetic hyperthermia for cancer therapy.

Long after the heady days of high‐temperature superconductivity, the oxides came back into the limelight in 2004 with the discovery of the 2D electron gas (2DEG) in SrTiO3 (STO) and several heterostructures based on it. Not only do these materials exhibit interesting physics, but they have also opened up new vistas in oxide electronics and spintronics. However, much of the attention has recently shifted to KTaO3 (KTO), a material with all the “good” properties of STO (simple cubic structure, high mobility, etc.) but with the additional advantage of a much larger spin‐orbit coupling. In this state‐of‐the‐art review of the fascinating world of KTO, it is attempted to cover the remarkable progress made, particularly in the last five years. Certain unsolved issues are also indicated, while suggesting future research directions as well as potential applications. The range of physical phenomena associated with the 2DEG trapped at the interfaces of KTO‐based heterostructures include spin polarization, superconductivity, quantum oscillations in the magnetoresistance, spin‐polarized electron transport, persistent photocurrent, Rashba effect, topological Hall effect, and inverse Edelstein Effect. It is aimed to discuss, on a single platform, the various fabrication techniques, the exciting physical properties and future application possibilities of this family of materials.

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