Magnetism in transition-metal-doped silicon nanotubes.
Using first-principles density functional calculations, we show that hexagonal metallic silicon nanotubes can be stabilized by doping with 3d transition metal atoms. Finite nanotubes doped with Fe and Mn have high local magnetic moments, whereas Co-doped nanotubes have low values and Ni-doped nanotubes are mostly nonmagnetic. The infinite Si24Fe4 nanotube is found to be ferromagnetic with nearly the same local magnetic moment on each Fe atom as in bulk iron. Mn-doped nanotubes are antiferromagnetic, but a ferrromagnetic state lies only 0.03 eV higher in energy with a gap in the majority spin bands near the Fermi energy. These materials are interesting for silicon-based spintronic devices and other nanoscale magnetic applications.
Singh
Abhishek Kumar
AK
Institute for Materials Research, Tohoku University, Aoba-ku, Sendai 980-8577, Japan.
Briere
Tina M
TM
Kumar
Vijay
V
Kawazoe
Yoshiyuki
Y