Research Projects

The emergence of altermagnetism introduces a fundamentally new magnetic phase that bridges the benefits of two conventional magnetic phases, i.e., ferromagnetism and antiferromagnetism. Altermagnets possess a spin-splittig in electronic band structure like ferromagnets but exhibit zero net magnetization like antiferromagnets. This combination enables spin-polarized transport without generating stray magnetic fields, making altermagnets exceptionally attractive for spintronic technologies that require both high efficiency and minimal magnetic interference. Despite theoretical advancements and early experimental confirmations, the field of altermagnetism remains in its initial stage, particularly concerning its material realization and integration into functional devices. Very few altermagnetic compounds have been experimentally synthesized and characterized to date. Moreover, their incorporation into device architectures such as spin valves, memory elements, or logic gates remains largely unattempted. Therefore, the field lacks comprehensive studies that connect materials synthesis, altermagnetism characterization, and functional device performance. The scientific objective of the proposal is to overcome these challenges by investigating the high-quality single crystals and thin films of Co- and Cr-doped FeSb₂, which are theoretically predicted to host altermagnetism. Along with this, we aim to increase the Néel temperature of altermagnet MnTe by substituting V/Cr at Mn sites, while ensuring the robustness of altermagnetism. We will use anomalous Hall effect (AHE) and anomalous Nernst effect (ANE) measurements as sensitive probes for detecting altermagnetic behavior in the synthesized materials. Also, to examine the potential of altermagnetism in spin-valve application, we will design and test CrSb and other altermagnets-based spin-valve heterostructures. To address the above objectives, the proposal combines theoretical and experimental approaches. Density functional theory (DFT) calculations using Quantum Espresso and Wannier90 will be used to model electronic structures, compute Berry curvature and associated anomalous Hall (AHC) and anomalous Nernst conductivities (ANC) as key transport signatures. Co-/Cr-doped FeSb₂, Mn₁₋ₓVₓ/CrₓTe, and CrSb will be synthesized as single crystals (via CVT) and thin films (via magnetron sputtering). Structural and magnetic characterizations will be performed using XRD, XRR, EDX, and SQUID-VSM. Angle-dependent Anomalous Hall Effect (AHE) and Anomalous Nernst Effect (ANE) measurements will be carried out using the existing Electrical Transport Option (ETO) and the proposed Thermal Transport Option (TTO), which is being requested under this project, in the PPMS system. Additionally, we will fabricate distinct spin-valve heterostructures using synthesized altermagnets ( for e.g. for CrSb altermagnet: Py/Cu/CrSb, Py/CrSb/Py, PMN-PT/CrSb/Py and BFO/CrSb/Py) and measure the magnetoresistance (GMR) of the devices, bridging material properties with functional device applications. The significance of this research lies at the frontier of next-generation spintronics by leveraging the benefits of altermagnets in future devices. From a fundamental perspective, this research will deepen our understanding of symmetry-driven magnetic phases and their transport behavior. On the applied front, the development of functional altermagnet-based spin-valve devices will represent a significant leap toward interference-free spintronic components. By integrating material discovery, fundamental characterization, and device realization in a single cohesive effort, this project aims to establish altermagnets as a viable materials platform for future spin-based technologies.