Prakash Chandra Srivastava

Biography

Current Research Projects: S. No. Name of the Project Duration Source of Funding Amount of Funding (Rs) 1. A study on nano granular magnetic phase embedded in semiconductor for Spintronics. 2007- 2010 DST, New Delhi 35.0 lacs Academic Qualifications: S. No. Degree Institution Year 1. B.Sc. Banaras Hindu University 1968 2. M.Sc. Banaras Hindu University 1970 3. Ph. D. Banaras Hindu University 1976

Research Interest

Our field of research is basically focused to see the spin polarized transport across magnetic metal-semiconductor interface, role of exchange bias phenomenon in FM/AFM or AFM/FM coupled systems. Our research studies include: (a) Interfacial Nanomagnetism for Spintronics: The research interest in nanomagnetism is motivated by the need for a better understanding of the fundamental principles that govern magnetic behavior, as well as the need for designing new magnetic materials for device application. Magnetic nanoparticles, compared to bulk materials, show unique physical properties such as superparamagnetism or enhanced anisotropy constants. Very little is known about the magnetization distribution within a single particle and magnetic correlations in ordered arrangements of such nanoparticles. The discovery of the giant- and tunnel magnetoresistance (GMR and TMR), i.e. the fact that the transport properties through an interface depend strongly on the magnetic properties of that interface, has revolutionized modern device technology. The quantum mechanical description of transport through an interface allows a detailed understanding of magnetic tunnel junctions used in spin- and magnetoelectronics. (b) Layered Magnetism with AFM/FM or FM/AFM interface: The exchange coupling across antiferromagnetic (AFM)/ferromagnetic (FM) or FM/AFM interface has been a fascinating topic in the recent past. Such nanostructures provide interesting physics and innovative ideas for a new generation of magnetic storage devices, magnetic field sensors and state of the art 'spintronic' devices. The exchange bias (EB) effect has been generally considered as an interfacial effect, implying that only interfacial spins are responsible for the unidirectional pinning of the magnetization of the FM layer. (c) Material modifications by swift heavy ion irradiation: Ion irradiation in magnetic thin films has shown interesting and intriguing phenomena like structural evolution etc. Ion irradiation of magnetic bilayers and multilayers has shown to modify the extrinsic magnetic properties, such as magnetic anisotropy, coercivity and magnetic exchange coupling. Ion irradiation is also known to cause interfacial mixing to relax the strain at the interface. (d) Magnetism in Semiconducting Materials: The semiconducting materials which exhibit both magnetism and semiconducting properties are known as magnetic semiconductors. Since, the traditional electronics is based on control of charge carriers (i.e., n- or p- type), but these magnetic semiconductors could provide a new type of conduction. This will also allow control of quantum spin state (up or down). This would theoretically provide near-total spin polarization, which is an important property for spintronics applications, eg. in spin transistors.