Understanding the physics behind various nanoscopic, mesoscopic and bulk magnetic materials and realization of their usage in practical devices such spin-electronics, opto-electronics, semiconducting devices, nano-electronics, ultrasonics and bioscience is one of the aims of my present research. Fundamentally, novel properties emerge in magnetic elements as the material dimensions become comparable to or smaller than certain characteristic length scales, such as spin diffusion length, carrier mean free path, magnetic exchange length, domain wall width, etc. When the size of magnetic material reduces, the magnetic properties of them would alter based on their dimensions. Such a strong dependence on the geometry allows one then to tailor the magnetization configuration by appropriately engineering the geometry. In addition, under extreme conditions such as very low temperatures, high magnetic fields and high pressures, one can realize quantum effects. Under these extreme and normal conditions understanding the structural, magnetic, electrical and optical properties are of great interest.