
5-1
Superconducting quantum interference devices (SQUIDs) have been a key factor in the development
and commercialization of ultrasensitive electric and magnetic measurement systems. In many cases,
SQ
UID
in
strumentation
o
ers
th
e
ab
ility
to ma
ke
me
asurements
wh
ere
no ot
her
me
thodology
is po
s-
sible
. In ad
dition
to me
asuring
ma
gnetic
e
lds,
SQ
UID
se
nsors
ca
n
be co
ngured
to me
asure
a wi
de
va
riety
o
f
e
lectromagnetic
p
roperties
.
Because of their superconducting nature, SQUID sensors operate at cryogenic temperatures.
Al
though
SQ
UID
el
ectronics
ha
ve
th
e
ca
pability
to op
erate
we
ll
ab
ove
1 MH
z,
mo
st
ap
plications
te
nd
to be at lower frequencie ...