Enabling Innovation Through Better Measurement Tools

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Module 9
, Version
5
.6 of
2/1
7
/201
3 [
artifact
clarifications
, in
-
case labels,

and better
pictures only;
no changes to panel text

or illustrations
]



Enabling Innovation Through
Better Measurement Tools


F1:

NIST continually
creates and
improves measurement tools need
ed for
innovation in
science, engineering, and commerce
.


F2:


Through Measurement to Knowledge”

(quotation

from an address by Dutch physicist
and Nobel Laureate Kamerlingh Onnes in 1882, translated by Arno Laesecke, NIST
Boulder
)
.


H1:

Putting Superconductivity to
Use

for Precision Measurements


B1:

Beams and pulses of light are key to a host of scientific and engineering research. Faint
light from stars and galaxies needs to be measured at many wavelengths (colors) from
microwave to infrared to visible to gamma rays. And
precisely measured
pulses o
f light
are crucial to state
-
of
-
the
-
art clocks, telecommunications, and the develo
p
ment of
quantum computers.


How can scientists and engineers measure amounts of light when every single photon
(the smallest unit of light) counts, across a broad range of c
olors?


In the 1990’s
NIST researcher
s

began experimenting with “
t
ransition
e
dge
s
ensors,”
light
detector
s

that work

because of the extreme

sensitivity
of tiny, thin superconducting films.
These metal films, coo
led to near
absolute
zero temperatures, are able to
carry small
electric currents with
no
resistance. But
that superconducting state is extremely fragile.
I
f the

films
are

warmed up by even a tiny pulse of light energy

from a single photo of
light
, they temporarily lose thei
r superconductivity
, and the loss can be detected
electronically
.


A1:


[
2002 Single
-
photon detector (currently in the Building 1 lobby display)

displayed
with
photo

alongside

identifying key component
.

3cm wide, 2 cm high, 18 mm deep, 6
-
7 oz.
]

[suggested magnification
10X (magnify only the chip at the center of the box)
]






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L1:

This
2002 transition edge
sensor
(TES)
could detect a single photon of light with 20%
efficiency.
By 2010
NIST
had created
TES

single photo
n

detectors
with
about
99%
efficiency

that worked

50 times faster
.


B2:

In the first decade of the 21
st

century NIST developed a variety of transition edge sensors
for different applications. Many telescope cameras and a commercial instrument
s

use
sensors based on NIST designs.


P1:





L2:

This microscopic
-
size sensor contains 4 transition edge sensors, the small rectangles near
the center.


A2:

(object pictured in P2
, displayed with photo P2 alongside identifying key elements; 1”
wide, 1/2”
high, ½” deep, 6
-
7 oz.
)

[suggested magnification

10X (this
item
could be
magnified with two glasses from two directions if desired)
]


P2:



L2

NIST Boulder developed superconducting instruments to detect gamma rays and alpha
particles from nuclear materials. These experimental instruments
were

designed for
verification of nuclear nonproliferation treaties and homeland security applications.

This
is NIST’s original
2006

gamma ray detector, which has one superconducting transition
edge

sensor

(TES)
.



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A3:

[2 cm wide, 2 cm high, less than 1 oz.]

[suggested magnification

10X (entire chip fits under
the glass
)]




L3:

A

more sophisticated
(2010
)
gamma ray detector, sister chip to the world
-
record gamma
ray detector now used by
the
Lo
s Alamos National Lab. The little squares are tin
absorbers, each glued on top of a TES sensor
.



H2:

SQUIDs


A4:

[3”
diameter, very thin,
less than 1 oz.]

[suggested magnification
6X (
cool view, and
most
of the wafer fits under this glass
)]





L4:

SQUID “read out” amplifier device.
To "read out"
signals from
the transition edge
sensors requires an incredibly sensitive amplifier. NIST developed
amplifiers based on a

related technology called SQUID
s

(
S
uperconducting
Q
uantum
I
nterference
D
evice
s
)
that
are able to read out
the information detected by
large arrays of
TES
sensors for use in
fields as diverse as astronomy, nuclear forensics, and
materials analysis.

The
combination of TES sensors and SQUID amplifiers makes
a supersensitive quantum
equivalent of the sensors in ordinary digital cameras,
but
capable of
recording images of
the faintest light emitting objects.



A5:

[
2” wide, .25” high, less than 1 oz.]

[suggested magnification
10X (magnify only the center
chip)
]



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L5:


NIST physicist Kent Irwin developed the use of DC
-
SQUIDs as low
-
power, low
-
noise
amplifiers for
transition
-
edge sensors, especially large arrays of sensors used in
astronomy, cosmology, materials analysis, and nuclear physics. The small rectangle in
the center of this device contains 100 SQUID amp
l
ifier/readouts

(
circa
200
0
-
2010
).



A6 [4 1/8”
long, 1 5/8” max. diameter
, 1 lb 5.6 oz.]

[
A7

deleted from list]





L6:


Multi
-
hole r
adio
-
frequency SQUID

made by NIST’s Jim Zimmerman in the 1970’s










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A8:

[7.35” wide, 1.5” high, 2.25” deep, 1 lb 12.5 oz.]



L7
:

Radio frequency electronics made by Jim Zimmerman to operate
an
early RF SQUID in
the 1970’s


A9:

[1 cm wide, 3 cm high, .5 cm deep, less than 1 oz.]






L8:

Jim Zimmerman, Ron Ono and
Jim Beall of NIST created t
he first radio
-
frequency
SQUID made with high
-
temperature superconductors

in 1987.

Connected to electronic
read
-
outs, it was so sensitive to changes in the magnetic field around itself that it could
detect the researchers’ heart
beats and the changing magnetic field if chairs were moved
around the room.


Th
is

sensor showcases Zimmerman’s genius as a master of simplification, using a
mechanical method to interrupt the superconducting (resistance free) flow of electricity.
The devic
e makes a controllable Josephson junction by fracturing the material and then
bringing the broken surfaces back together, simultaneously allowing electrons to leap
across the break and enabling measurements of the signals.


P3:



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L9
:

Jim Zimmerman,
Jim Beal, and
Ron Ono
(left to right)
, early1970’s
. The red box

visible
in this photograph is o
n display in this exhibit
. The box

contains the

electronics to
control the SQUID dev
ice.


H3:

Superconducting Cameras


B3:

NIST buil
t

superconducting

cameras to make images of the cosmic microwave
b
ackground, seeking signs of the rapid inflation of the universe just after the Big Bang
13.7 billion years ago. A NIST

camera containing hundreds of cosmic microwave
b
ackground
detectors
began operating at t
he
South Pole Telescope

in 20
12
.


P
4:





L10:

The South Pole Telescope uses a camera that
includes
TES detectors
made by Dale Li at
NIST Boulder

in 2011
.




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A10:

[2 cm wide, 1 cm high, 2 cm deep, 5 oz.

Photo
P5, showing the core of the device and
identifying components, should be placed alongside.
]
[suggested magnification 10X]







P5:





L11
:

This
2010

prototype
detector

had
two
TES
superconducting sensors
, enlarged in the
photo
. The

sensors are made of a bilayer of normal metal (copper) and superconducting
metal (molybdenum) that changes its resistance to electricity in response to the
tiny
amount of
heat from cosmic radiation

collected by a telescope. This
was
a prototype for
an arr
ay of sensors to study light
from
the
very early history of the
universe
.

In 2012
seven arrays of 84 sensors each were installed
in

the South Pole Telescope.





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H4:

Setting the volt


A11:

[
10.3 cm wide, 10.3 cm deep, 13 cm

high
, 1.5 pounds. Label: Standard cell, case cut
away to show interior.
]





L12:

For most of the 20
th

century, the practical standard for measuring a volt was a chemical
standard cell, like the one here. It was a simple battery with very stable voltage
, and fine
for calibrating everyday meters

but
was
not stable enough

for the highest precision
work
. Ag
ing and temperature
differences
change
d

its voltage
,

making this standard
unacceptable for the high
accuracy required i
n the
electronic
age.


A12:

[
in case measures 10.3 x 7 x .7 cm
]
[suggested magnification

10X]




L13:


In 1985 NIST invented the first practical, stable, and easy to use high accuracy voltage
standard
. It
took advantage of the basic quantum physics of
a unique superconducting
electronic device called a Josephson junction.
No chemical reactions were involved.


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Each
Josephson junction

produces only a tiny voltage, so this
quantum

standard used
1,484 microscop
ic

Josephson
junctions to produce a
1
-
volt

dc standard.


Four years later, NIST made a
10
-
volt

standard, with 14,184 junctions
, which is now
commercially available and is the world's standard for voltage
.



B4:

In 1996, NIST researcher
Sam

Benz

and colleagues at Westinghouse Electric devised a
way to create a quantum voltage standard
device
for ac

voltages.




[Objects

A13
and A14
are
3
additional examples of quantum
-
based voltage standards, with
illumination and a large magnifying glass. Each
is
labeled
in the display case
with a
date
and very short description
.
O
bject A 15

has been deleted
.



A13: [
wafer
7.5 cm dia
.

In
-
case l
abel:
A set of
1 volt programmable standards on a wafer,
1997
]
[magnification could be either 6X for more of the wafer, or 10X
of a small area]







A14:
[In case 12cm x 8.3 cm x 1.5 cm.
In
-
case l
abel: 10 volt programmable standard,
2010]
[suggested magnification 10X]





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P6:

[
http://patapsco.nist.gov/imagegallery/details.cfm?imageid=845
]






L14:

NIST researchers continue to make increasingly capable
quantum
voltage standards,
which are expanding the applications that take advantage of
extreme

quantum
-
level

accuracy.

This 2010 10
-
volt AC/DC standard contains about 300,000 superconducting
Josephson junctions loca
t
ed along the horizontal lines on the right in this
microphotograph
.





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H5:

Thermometers in the sky


B5:

Accurate temperature measurements are critical for

weather forecasting,
climate studies,
ecological surveys, agriculture, and national defense
(such as
loca
ting
clandestine
underground facilities
)
.


Since
the 1970s
m
icrowave

(radar)

thermal
“noise”
signals
from the Earth’s surface,
collected in the upper atmosphere by aircraft
and

satellites
,

have been used
to
monitor
changes in Earth temperatures. But by 2005, scientists
noticed
significant
discrepancies
a
mong data on temperature from different climate research projects over the same period.
Which of the
microwave
measurements were the most accurate?


NIST’s m
icrowave measurement research programs, begun in 1944, were moved
from
Washington, DC to
the new
Boulder
site, dedicated
in 1954.

The
Boulder facility was
established
i
n part to study radio wave propagation and develop the measurement basis
for all high frequency electromagnetic wave technology.


P7:






P8:






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L15
:

NIST’s Doug Kremer

c
alibrating an A
irborne Warning and Control System (A
WACS
)

radar antenna
at NIST Boulder
for the US Air Force
E3 Sentry airplane
in
1984.

The
antenna is 30 f
eet

wide by 3 feet high.



B6:

In 2001 NIST Boulder’s James Randa and David Walker and their team began research
to
reduce

discrepancies in
microwave
-
based
Earth
-
temperature data. Their goal was to
enable all the users of microwave remote sensing worldwide to trace the calibration of
th
eir instruments back to NIST
-
based standards. NIST began providing calibration
services, while at the same time developing a superior new standard for measuring
radiated thermal noise. In 2012, NIST was ready to present a new standard to the
internationa
l community.


P9:





L16:

calibrating a microwave receiver for NOAA


A16:

[4” wide,
4
.5


high, 4” deep,
under 1

lbs.]





L17:

This special machined and coated
surface was
designed to
minimize reflection of specific
microwave frequencies for
NIST’s calibration facility.





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A17:


[
8.5 inches by 9.5 inches by 3 inches high.
;

base alone 23.6cm x 21.5cm x 2cm high
]




L18:

A radiating source used
as a transfer standard for calibrating a
irborne
microwave sensors.
NIST calibrates transfer standards like these using its special
facilit
ies

and expertise.
NIST contributed significantly to the science an
d practice of such measurements

worldwide.



P10:





L19
:

Th
ese primary Cryogenic Thermal
Noise Standards developed by NIST

beginning in the
1980s

serve as the basis for all microwave noise temperature measurements. Each of
these standards covers a different frequency range. These standards, which NIST
continues to research and improve, suppor
t scientific research and commercial
development worldwide.