2005/11/28 by F. P. Mena, J. F. DiTusa, D. van der Marel +5 · 22 citations
Chemistry · Physics and Astronomy · #Carrier scattering #Charge carrier #Chemistry #Condensed matter physics #Coulomb #Doping #Electron #Magnetic properties of thin films #Magnetic semiconductor #Materials science #Optics #Optoelectronics #Paramagnetism #Physics #Polarization (electrochemistry) #Quantum and electron transport phenomena #Quantum mechanics #Scattering #Semiconductor #Semiconductor materials and interfaces #Spin (aerodynamics) #Spin polarization #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.73.085205
published in Physical Review B 73(8) (American Physical Society) · 6 figures Submitted to PRB
arxiv created 2005/11/28 · openalex publication_date 2006/02/17 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The narrow gap semiconductor FeSi owes its strong paramagnetism to electron-correlation effects. Partial Co substitution for Fe produces a spin-polarized doped semiconductor. The spin polarization causes suppression of the metallic reflectivity and increased scattering of charge carriers, in contrast to what happens in other magnetic semiconductors, where magnetic order reduces the scattering. The loss of metallicity continues progressively even into the fully polarized state, and entails as much as a 25% reduction in average mean-free path. We attribute the observed effect to a deepening of the potential wells presented by the randomly distributed Co atoms to the majority spin carriers. This mechanism inverts the sequence of steps for dealing with disorder and interactions from that in the classic Al'tshuler Aronov approach---where disorder amplifies the Coulomb interaction between carriers---in that here, the Coulomb interaction leads to spin polarization which in turn amplifies the disorder-induced scattering.