<s>
Perpendicular	B-Device
recording	I-Device
(	O
or	O
perpendicular	B-Device
magnetic	I-Device
recording	I-Device
,	O
PMR	O
)	O
,	O
also	O
known	O
as	O
conventional	O
magnetic	B-Architecture
recording	I-Architecture
(	O
CMR	O
)	O
,	O
is	O
a	O
technology	O
for	O
data	O
recording	O
on	O
magnetic	B-Architecture
media	I-Architecture
,	O
particularly	O
hard	B-Device
disks	I-Device
.	O
</s>
<s>
The	O
first	O
industry-standard	O
demonstration	O
showing	O
unprecedented	O
advantage	O
of	O
PMR	O
over	O
longitudinal	O
magnetic	B-Architecture
recording	I-Architecture
(	O
LMR	O
)	O
at	O
nanoscale	O
dimensions	O
was	O
made	O
in	O
1998	O
at	O
IBM	O
Almaden	O
Research	O
Center	O
in	O
collaboration	O
with	O
researchers	O
of	O
(	O
DSSC	O
)	O
–	O
a	O
National	O
Science	O
Foundation	O
(	O
NSF	O
)	O
Engineering	O
Research	O
Center	O
(	O
ERCs	O
)	O
at	O
Carnegie	O
Mellon	O
University	O
(	O
CMU	O
)	O
.	O
</s>
<s>
Perpendicular	B-Device
recording	I-Device
can	O
deliver	O
more	O
than	O
three	O
times	O
the	O
storage	B-Device
density	I-Device
of	O
traditional	O
longitudinal	O
recording	O
.	O
</s>
<s>
In	O
1986	O
,	O
Maxell	O
announced	O
a	O
floppy	B-Device
disk	I-Device
using	O
perpendicular	B-Device
recording	I-Device
that	O
could	O
store	O
.	O
</s>
<s>
Perpendicular	B-Device
recording	I-Device
was	O
later	O
used	O
by	O
Toshiba	O
in	O
3.5	B-Device
"	I-Device
floppy	I-Device
disks	I-Device
in	O
1989	O
to	O
permit	O
2.88	O
MB	O
of	O
capacity	O
(	O
ED	O
or	O
extra-high	B-Device
density	I-Device
)	O
,	O
but	O
they	O
failed	O
to	O
succeed	O
in	O
the	O
marketplace	O
.	O
</s>
<s>
Since	O
about	O
2005	O
,	O
the	O
technology	O
has	O
come	O
into	O
use	O
for	O
hard	B-Device
disk	I-Device
drives	I-Device
.	O
</s>
<s>
Hard	B-Device
disk	I-Device
technology	O
with	O
longitudinal	O
recording	O
has	O
an	O
estimated	O
limit	O
of	O
due	O
to	O
the	O
superparamagnetic	O
effect	O
,	O
though	O
this	O
estimate	O
is	O
constantly	O
changing	O
.	O
</s>
<s>
Perpendicular	B-Device
recording	I-Device
is	O
predicted	O
to	O
allow	O
information	O
densities	O
of	O
up	O
to	O
around	O
.	O
</s>
<s>
Perpendicular	B-Device
recording	I-Device
uses	O
higher	O
coercivity	O
materials	O
because	O
the	O
head	O
's	O
write	O
field	O
penetrates	O
the	O
medium	O
more	O
efficiently	O
in	O
the	O
perpendicular	O
geometry	O
.	O
</s>
<s>
The	O
popular	O
explanation	O
for	O
the	O
advantage	O
of	O
perpendicular	B-Device
recording	I-Device
is	O
that	O
it	O
achieves	O
higher	O
storage	B-Device
densities	I-Device
by	O
aligning	O
the	O
poles	O
of	O
the	O
magnetic	O
elements	O
,	O
which	O
represent	O
bits	O
,	O
perpendicularly	O
to	O
the	O
surface	O
of	O
the	O
disk	O
platter	O
,	O
as	O
shown	O
in	O
the	O
illustration	O
.	O
</s>
<s>
This	O
is	O
possible	O
because	O
in	O
a	O
perpendicular	O
arrangement	O
the	O
magnetic	O
flux	O
is	O
guided	O
through	O
a	O
magnetically	O
soft	O
(	O
and	O
relatively	O
thick	O
)	O
underlayer	O
underneath	O
the	O
hard	O
magnetic	B-Architecture
media	I-Architecture
films	O
(	O
considerably	O
complicating	O
and	O
thickening	O
the	O
total	O
disk	B-Device
structure	I-Device
)	O
.	O
</s>
<s>
This	O
magnetically	O
soft	O
underlayer	O
can	O
be	O
effectively	O
considered	O
a	O
part	O
of	O
the	O
write	O
head	O
,	O
making	O
the	O
write	O
head	O
more	O
efficient	O
,	O
thus	O
making	O
it	O
possible	O
to	O
produce	O
a	O
stronger	O
write	O
field	O
gradient	O
with	O
essentially	O
the	O
same	O
head	O
materials	O
as	O
for	O
longitudinal	O
heads	O
,	O
and	O
therefore	O
allowing	O
for	O
the	O
use	O
of	O
the	O
higher	O
coercivity	O
magnetic	B-Architecture
storage	I-Architecture
medium	O
.	O
</s>
<s>
In	O
the	O
early	O
2000s	O
,	O
three	O
important	O
factors	O
came	O
together	O
which	O
allowed	O
perpendicular	B-Device
recording	I-Device
to	O
exceed	O
the	O
capabilities	O
of	O
longitudinal	O
recording	O
and	O
led	O
to	O
commercial	O
success	O
.	O
</s>
<s>
5	O
MB	O
removable	O
floppy	B-Device
drives	I-Device
were	O
demonstrated	O
in	O
IBM	O
PCs	O
to	O
major	O
computer	O
manufacturers	O
.	O
</s>
<s>
Shortly	O
thereafter	O
in	O
January	O
2006	O
,	O
Seagate	O
Technology	O
began	O
shipping	O
its	O
first	O
laptop	O
sized	O
hard	B-Device
drive	I-Device
using	O
perpendicular	B-Device
recording	I-Device
technology	I-Device
,	O
the	O
Seagate	O
Momentus	O
5400.3	O
.	O
</s>
<s>
Seagate	O
also	O
announced	O
at	O
that	O
time	O
that	O
the	O
majority	O
of	O
its	O
hard	B-Device
disk	I-Device
storage	I-Device
devices	O
would	O
utilize	O
the	O
new	O
technology	O
by	O
the	O
end	O
of	O
2006	O
.	O
</s>
<s>
In	O
April	O
2006	O
,	O
Seagate	O
began	O
shipping	O
the	O
first	O
3.5inch	O
perpendicular	B-Device
recording	I-Device
hard	B-Device
drive	I-Device
,	O
the	O
Cheetah	O
15K.5	O
,	O
with	O
up	O
to	O
300GB	O
storage	O
,	O
running	O
at	O
15,000	O
rpm	O
and	O
claim	O
to	O
have	O
30%	O
better	O
performance	O
than	O
their	O
predecessors	O
with	O
a	O
data	O
rate	O
of	O
73	O
–	O
125	O
Mbyte/s	O
.	O
</s>
<s>
In	O
April	O
2006	O
,	O
Seagate	O
announced	O
the	O
Barracuda	O
7200.10	O
,	O
a	O
series	O
of	O
HDDs	O
utilizing	O
perpendicular	B-Device
recording	I-Device
with	O
a	O
maximum	O
capacity	O
of	O
750	O
GB	O
.	O
</s>
<s>
Hitachi	O
announced	O
a	O
20	O
GB	O
Microdrive	B-Device
.	O
</s>
<s>
Hitachi	O
's	O
first	O
laptop	O
drive	O
(	O
2.5-inch	O
)	O
based	O
on	O
perpendicular	B-Device
recording	I-Device
became	O
available	O
in	O
mid-2006	O
,	O
featuring	O
a	O
maximum	O
capacity	O
of	O
160	O
GB	O
.	O
</s>
<s>
In	O
June	O
2006	O
,	O
Toshiba	O
announced	O
a	O
hard	B-Device
drive	I-Device
of	O
200-GB	O
capacity	O
with	O
mass	O
production	O
starting	O
in	O
August	O
,	O
effectively	O
raising	O
the	O
standard	O
of	O
mobile	O
storage	O
capacity	O
.	O
</s>
<s>
In	O
July	O
2006	O
,	O
Western	O
Digital	O
announced	O
volume	O
production	O
of	O
its	O
WD	O
Scorpio	O
hard	B-Device
drives	I-Device
using	O
WD-designed	O
and	O
manufactured	O
perpendicular	B-Device
magnetic	I-Device
recording	I-Device
(	O
PMR	O
)	O
technology	O
to	O
achieve	O
80	O
GB-per-platter	O
density	O
.	O
</s>
<s>
In	O
August	O
2006	O
Fujitsu	O
extended	O
its	O
lineup	O
to	O
include	O
SATA	O
models	O
utilizing	O
perpendicular	B-Device
recording	I-Device
,	O
offering	O
up	O
to	O
160GB	O
capacity	O
.	O
</s>
<s>
In	O
December	O
2006	O
Toshiba	O
said	O
its	O
new	O
100GB	O
two-platter	O
HDD	O
is	O
based	O
on	O
perpendicular	B-Device
magnetic	I-Device
recording	I-Device
(	O
PMR	O
)	O
and	O
was	O
designed	O
in	O
the	O
"	O
short	O
"	O
1.8-inch	O
form	O
factor	O
.	O
</s>
<s>
In	O
December	O
2006	O
Fujitsu	O
announced	O
its	O
MHX2300BT	O
series	O
of	O
hard	B-Device
disk	I-Device
drives	I-Device
,	O
with	O
capacities	O
of	O
250	O
and	O
300	O
GB	O
.	O
</s>
<s>
In	O
January	O
2007	O
Hitachi	O
announced	O
the	O
first	O
1-terabyte	O
hard	B-Device
drive	I-Device
using	O
the	O
technology	O
,	O
which	O
they	O
then	O
delivered	O
in	O
April	O
2007	O
.	O
</s>
<s>
In	O
July	O
2008	O
Seagate	O
Technology	O
announced	O
a	O
1.5	O
terabyte	O
SATA	O
hard	B-Device
drive	I-Device
using	O
PMR	O
technology	O
.	O
</s>
<s>
In	O
January	O
2009	O
Western	O
Digital	O
announced	O
the	O
first	O
2.0	O
terabyte	O
SATA	O
hard	B-Device
drive	I-Device
using	O
PMR	O
technology	O
.	O
</s>
<s>
In	O
February	O
2009	O
Seagate	O
Technology	O
announced	O
the	O
first	O
7,200	O
rpm	O
2.0	O
terabyte	O
SATA	O
hard	B-Device
drive	I-Device
using	O
PMR	O
technology	O
with	O
choice	O
of	O
SATA	O
2	O
or	O
SAS	O
2.0	O
interface	O
.	O
</s>
