Synthesis and study of structural optical and magnetic properties of ZnO based diluted magnetic semiconductor nanoparticles

Abstract

Semiconductors are defined by their unique electrical conductivity, somewhere newlinebetween that of a metal and an insulator. The difference between these materials can newlinebe understood in terms of the band gap between the available quantum states for newlineelectrons (each of the quantum state may contain zero or one electron according to newlinethe Pauli s exclusion principle). These states are associated with the electronic band newlinestructure of the material. In order to transport electrons, a state must be partially filled newlineor vacant and the band gap must be feasible for the transfer. A state is partially filled newlineonly if its energy is near to the Fermi level. An intrinsic semiconductor is not very newlineuseful. However, its usefulness can be increased and modulated by doping the host newlinesemiconductor with different elements. The conduction or valence band moves closer newlineto the Fermi level due to doping which increases the number of partially filled states. newlineFor example, some wide-band gap semiconductor materials (sometimes referred to newlineas semi-insulators), have electrical conductivity very near to that of electrical newlineinsulators in intrinsic form, however, they can be doped to make them useful newlinesemiconductors for various practical application. newlineMagnetic semiconductors are semiconductor materials that exhibit newlineferromagnetic properties (or a similar response) along with the semiconductor newlineproperties. These materials could exhibit a new type of transport phenomena if newlineimplemented practically in devices. These magnetic semiconductors allow for the newlineactive control and manipulation of the spin degree of freedom (quantum spin state of newlineup or down) of electrons, instead of or in addition to, their charge degree of freedom, newlinein contrast to conventional electronics where only charge degree of freedom is utilized newlinefor device operations. This may provide option for spin polarization which is an newlineimportant requirement for spintronic-based applications, for example, spin transistors. newlineTo that end, dilute magnetic semiconductors (DMSs) have recently been a major newlinefocus of magnet