International Journal of
Physical Sciences

  • Abbreviation: Int. J. Phys. Sci.
  • Language: English
  • ISSN: 1992-1950
  • DOI: 10.5897/IJPS
  • Start Year: 2006
  • Published Articles: 2577

Full Length Research Paper

Enhancement of TC of the (Ga,Mn) As diluted magnetic semiconductor by photoinduced exchange coupling of the Mn2+ spins

Chernet Amente and P. Singh
Department of Physics, Addis Ababa University, P. O. Box 1176, Addis Ababa, Ethiopia.
Email: [email protected]

  •  Accepted: 30 April 2010
  •  Published: 30 June 2010

Abstract

Effect of photo-excitation on the ferromagnetic transition temperature TC of the diluted magnetic semiconductor (DMS) (Ga,Mn) As is theoretically studied. The model Hamiltonian used to describe the system consists of interaction of localized Mn2+ spins with radiation field as appropriate to ferromagnetic and/or spin wave resonance. Using second order perturbation theory, an expression for photoinduced exchange coupling energy between the Mn spins is obtained. It is argued that the coupling energy could be significantly large to provide very large TCat/near spin wave resonance. The intensity and energy of the light can further assist enhancement of TC useful for high temperature spintronic devices. An analogy with carrier mediated Ruderman-Kittel-Kasuya-Yosida (RKKY) type interaction with magnetic ions is also established.

 

Key words: Spintronics, (Ga,Mn)As, exchange coupling, photo-excitation, resonance, ferromagnetism, DMS.