The inevitable slowing down of Moore’s law will be a key hurdle for developing the next-generation of microelectronics. Spintronic and multiferroic materials have emerged as leading contenders for our future electronics.
Spintronics aims to enhance and replace standard charge-based electronics by harnessing the electron’s spin. ‘Half-metallic ferromagnets’, which exhibit metallic behavior for spin-up electrons and semiconducting behavior for spin-down, are rarely-occurring materials that can filter the spin of charge carriers, and therefore have excellent potential for spintronics. Work in our group predicted and explained half-metallic ferromagnetism in a new class of materials based on the BaMn2As2, and explained the failure of Fe spin injection in GaAs.
Materials that have more than one ferroic ordering at the same time are known as ‘multiferroics’. The hexagonal manganite class of multiferroics play host to a range of properties from the technologically relevant to being a model system for testing high- and low- energy theories. The group has used first-principles calculation, symmetry analysis and effective Hamiltonians to develop a universal description of topological defects, domains and domain-wall formation for the hexagonal-manganite multiferroics. We also predicted that ferroelectricity in the hexagonal manganites can be controlled using chemical defects from first-principles calculations, which was subsequently verified by experiments.