<s>
Bipolar	B-General_Concept
magnetic	I-General_Concept
semiconductors	I-General_Concept
(	O
BMSs	O
)	O
are	O
a	O
special	O
class	O
of	O
magnetic	O
semiconductors	O
characterized	O
by	O
a	O
unique	O
electronic	O
structure	O
,	O
where	O
valence	O
band	O
maximum	O
(	O
VBM	O
)	O
and	O
conduction	O
band	O
minimum	O
(	O
CBM	O
)	O
are	O
fully	O
spin	B-General_Concept
polarized	I-General_Concept
in	O
the	O
opposite	O
spin	O
direction	O
.	O
</s>
<s>
Up	O
to	O
now	O
,	O
bipolar	B-General_Concept
magnetic	I-General_Concept
semiconductors	I-General_Concept
,	O
together	O
with	O
half-metal	O
and	O
spin	O
gapless	O
semiconductor	O
,	O
have	O
been	O
viewed	O
as	O
three	O
important	O
classes	O
of	O
spintronic	O
materials	O
.	O
</s>
<s>
The	O
proposal	O
of	O
bipolar	B-General_Concept
magnetic	I-General_Concept
semiconductor	I-General_Concept
(	O
BMS	O
)	O
is	O
aimed	O
to	O
realize	O
electrical	O
control	O
of	O
carriers	O
 '	O
spin	O
orientation	O
,	O
which	O
is	O
a	O
key	O
scientific	O
problem	O
in	O
developing	O
high	O
performance	O
spintronics	O
devices	O
,	O
since	O
electric	O
field	O
can	O
be	O
easily	O
applied	O
locally	O
,	O
in	O
contrast	O
to	O
magnetic	O
field	O
.	O
</s>
