11 research outputs found
Bipolar Magnetic Semiconductors: A New Class of Spintronics Materials
Electrical control of spin polarization is very desirable in spintronics,
since electric field can be easily applied locally in contrast with magnetic
field. Here, we propose a new concept of bipolar magnetic semiconductor (BMS)
in which completely spin-polarized currents with reversible spin polarization
can be created and controlled simply by applying a gate voltage. This is a
result of the unique electronic structure of BMS, where the valence and
conduction bands possess opposite spin polarization when approaching the Fermi
level. Our band structure and spin-polarized electronic transport calculations
on semi-hydrogenated single-walled carbon nanotubes confirm the existence of
BMS materials and demonstrate the electrical control of spin-polarization in
them.Comment: 20 pages, 6 figures, accepted by Nanoscal