CRYOGENIC PARTICLE DETECTORS

Based on Superconducting Transition Edge Sensors

Blas Cabrera

February 19 and 26,1999

LECTURES #19 AND #20

Cryogenic Particle Detectors Based on

Superconducting Transition Edge Sensors

Blas Cabrera Physics Department, Stanford University

February 19,1999 and February 26, 1999

References:

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4.

5.

6.

7.

8.

“Low Temperature Particle Detectors”, N. Booth, B. Cabrera, and E. Fiorini, Annu. Rev. Nucl Part. Sci. 46, 471-532 (1996).

“A Quasiparticle-Trap-Assisted Transition-Edge Sensor for Phonon-Mediated Particle Detection”, K. D. Irwin, S . W. Nam, B. Cabrera, B. Chugg, and B. Young, Rev. Sci. Znstrum. 66, 5322-6 (1995).

“Bolemetric Sensors for Elementary Particle Detectors”, B. Cabrera, Sixth Interantional Workshop on Low Temperature Detectors, Bern, Switzerland, LTD6, Nucl. Instr. and Meth., A370 150-156 (1996).

“Charge Collection and Trapping in Low Temperature Silicon Detectors”, M, J. Penn, B. L. Dougherty, B. Cabrera, R. M. Clarke, and B. A. Young, J . Appl. Phys. 79, 8179-8186 (1996).

“A Superconducting Bolometer with Strong Electrothermal Feedback”, A. T. Lee, P. L. Richards, S . W. Nam, B. Cabrera, K. D. Irwin, and J. M. Martinis, Appl. Phys. Lett. 69, 1801-3 (1996).

“Operation of an Improved 100 g Si FLIP detector for the CDMS experiment”, R. M. Clarke, P. L. Brink, S. W. Nam, A. K. Davies, B. Chugg, B. A. Young, and B. Cabrera, Proceedings of the Seventh International Workshop on Low Temperature Detectors (LTD-7), held in Munich, Germany from 27 July to 2 August, 1997, pp. 229-23 1, (Max Planck Institute of Physics, 1997).

“Performance of first 100 g Si FLIP detector in the CDMS experiment”, A. K. Davies, P. L. Brink, R. M. Clarke, S . W. Nam, B. A. Young, and B. Cabrera, Proceedings of the Seventh International Workshop on Low Temperature Detectors (LTD-7), held in Munich, Germany from 27 July to 2 August, 1997, pp. 227-228, (Max Planck Institute of Physics, 1997).

“Detection of Single Infrared, Optical, and Ultraviolet Photons Using Superconducting Transition Edge Sensors”, B. Cabrera, R. M. Clarke, P. Colling, A. J. Miller, S. Nam, and R. W. Romani, Applied Physics Letters 73, 735-737 (1 998).

1

Particle Detectors. using Transition Edge Sensors Blas Cabrera - Stanford University

Motivation TES Operation - Voltage bias and electrothermal feedback - High resolution demonstrated

- F ibcoup4eb telescope observations - Fast photometry and large arrays

Optical photon detectors

X-Ray detectors - Best resolution for materids characterization

Dark Matter Search - Quasiparticle trap assisted phonon sensor - Status of CDMS (cryogenic dark matter search)

Summary and Conclusions

2

TES Technology

Demonstrated Sensitivity with TES

/ Resolution target G- ISCOfISh

M i m e t e r s

for Transition

I

LLNL STJ t Spectrometers

IO'

# >" 2 1 Edgesensors E \ NIST X-Ray TES Specbometers

100

c 0 3 .-.I * m

2 2 lo-'

- #

I .1 I 1 I I 10'' loo 10' lo2 io3 lo4

Photon Energy [eV]

NIST AVAu TES 3.1 eV FWHM @ 1.5 keV

Stanford W TES 0.15 eV FWHM @ 1.5 eV

A factor of 2-3 improvement is likely with an additional factor of 4 to the fundamental limit

Stanford o p b d # # /-- Fundamental limit for Tc = 70 mK

& # with 100% ETF efficiency

# # c # TESsensors e # # #

# # c 0 # #

# # c # # #

# A

/1

E 3-

V G

a

I

Y

a" m X cd

.- N

(

2c

40

60 Lev photon

recoil \ J'

60

-20 0 20 X axis (pm)

... 60 keV photon

recoil eiectron

J

-20 0 20 Y axis (pm)

1 o4 E s lo2 > 5 loo 3

I 0-6

..................... ........................... ............ ......... . ............. i

............ ......... ............

........... ............

10-l 10' lo3 lo5 io7 Electron Energy (eV)

5

3

0 3

1

0 3

1

0 0 1 4 5

0 20 40 60 80 100 Electric Field (V/cm)

e le c t ron 4 /

/phonon

7

Backscattered iotis = Traitsn i t ted Ions =

Range Strayg le

Latera 1 = 129 Long i tud i na 1 = 25%

Rad ia 1 = 18A Uac./Ion = 164.8 ENERGY LOSS(z1 IONS RECOILS Ionization => 25.84 26.18 Vacancies => 8.42 1.66

8

.-I$. I , - - _ _ ~ . --I--- - _-- . . ..

h -. . ;!* .

C

; E .- VI

I

RECOILS PHONONS I

IONS E 0 k I

c, in bo

8 - Depth ->

A

9

I I L

1 2 3 7 Frequency (THz)

2 A N

10

0.04

-- E bin

E t-

o .02

0

1 I I ' 1 ' 1 , 8 I I I I

0 0.5 I .o Time (ps)

1 1

1.5

, - --3 0.02 0 E bin /E total

n

0 0 d Y

... .. . . . . .

n

W

..' . . .' . . . . . . . . .

c1

d

... . . _. . , ..f

,. .. . .'

: .

' d

. . . . . . . . I :

0 : . . . . . . d . - ! : '. i : o n 1

. . . . , . . . . . , .; v ' .. m

- X <I- n - 0 0 Y

14

Transition Edge Sen.sors

Steep Resistive Supeconducting Transition

W Tc - 70-90 mK 10-90% < I mK

T .=-I- dR R / dT T

uni tless measure of transition width

Voltage bias is intrinsically stable

The Joule heating produced by bias

VB’ PJ 3. whenR t

is stable whereas for current bias

which is intrinsically unstable

< = i F

P , = I i R - PJ f whenRT

SQUID

R S shunt

16

ri. ? Q,

RC -\.pa

1 7

Thermal Model’

I pJ

Time -b c u photon

Electrothermal Feedback - Voltage bias intrinsically stable

- Past response - =0

- High Sensitivity g = nZTen-l 9 z o = - 9

C

g zecf - 1 + a / n

W W H M - - 2.3554-

For E sat (- C T / a ) e = 10 keV then AEwHM = 1.1 eV

For E,, (- C TJa) = 10 eV then LIE,,, = 42 meV IC! MeV I . ! - m c 7 -

Q \ e h s h t ‘ 1 ~ ~ ; # i ? g a % s 6, ~ m,

Operation of TES Sensors

I I 1

I # I ' 6

z? Y

0 PI

0 I

-600 -400 -200 0 200 400 600

Current Bias [PA]

19

Three Applications

Direct absorption of photon into TES (e. g., optical photon detectors) c/ 1-10eV photon

W Si or Ge

.. \ r

Photon absorber in electicd contact with TES (e. g., x-ray detectors)

Bi AVAg \ r,

1-10 keV x-ray r /

Si,N, 4 Large mass absorbers generate phonons which are converted into quasiparticles and the quasiparticles diffuse to the TES (e. g., dark matter detectors)

W AI \ Si or Ge

20

Optical Photon Detectors Demonstration of W TES sensitivitv

J

M acti ve i' sensc AI

voltage rai 1 s

0.6 I I I I I

I I

3 3 0.4- Y a3 C an c

?sub = 43.8341 mK .

Rshusc=O.Wohrns . Rkod = 0.005 ohms

-

6 0.3- 531 nm c photon

0.2-

a' 2 0.1 -

Y

Bias Cumnt [ItA]

6 Q) cn

'3"E 0

-0.1 ' I 1 I I I I 0 100 200 300 - 1 0 0

Time bsec]

Appl. Phys. Lett. A u,u IO. 1998, Cabrera, et al. L

Monochromator Calibrations

IR ih backeround L

2500

rai 1 B hits .- m

2nd order

Energy [eVI ,

I

3000-

2500-

m- (d Y

3 1500- u"

1OOO-

500-

23

c I I I I I I I 1 0.14 -

0.12 -

0.1 -

k' 0.08- 2 Y

E 0.06- p!

0.04-

0.02 -

L 3

-0.02 1

-I

(J

I I I

0 100 I I I I I I

200 300 400 500 600 700 800 Time (c(s]

Fiber-coupled Telescope Data

Fiber-coupled Celestron 8 - 98 06 16 2oOo.

1500r c ~1OOo: , 0

."+I 500-

0 --c_i--

0 100 200 300 400 500 600 700 800

"0 100 200 300 400 500 600 700 800

i NGC6572

1

100 200 300 400 500 600 700 800

I streetlamp

I 2200- i

100 - I

OO 100 200 300 400 500 600 700 800

First TES Observation of Crab Pulsar

1 -

Crab Pulsar, livetime = 1988 sec, period = 33.4938 msec 11 I I I I 1 I I

.. - . .

, I I 1 I 1 I I

n X 8 E

Y

s

i 20 :: 0 0 0.5 1 1.5 2 2 5 3 3.5 4

Energy Spectrum of Crab Pulsar 8 I I I r 1 I I

n *. 5 -

4 -

L 3 '

s 5 2 - E 2

i t -

O - I J ' , I I I

0 -0.5 1 1.5 2 2.5 3 3.5 4 i

Photon Energy [eV]

26

Histograms of Energy vs Phase

27

Histograms of Energy vs Phase

28

29

"

31

.j

TES X-Ray Detectors

ilecaj probabl! because energj h deposited in AI quasiparticle

68.5 1 2 1 I 3 681 ~ <> .;tern and released o w - a

First W TES on Ge test device

electron temperatw

J :,

I,

'L

quasi particles 25 prn A1 8 ,/ wirebonds 40 nm W TES I

P . A / " v 6 keV iy - ra v s

-\ 150pm by .5 mm square Ge

1 3 - I I

I

,- 1 coup1 ed electrons I

and phonons j

i decay time constanls j

sirnuhion with

4 I

,

produces t i l o

0 5 I 10

---

2.5 /,

/

I

P I

rr*b=l - os

0

4 s 0 :5 I l:5 2 2:5 3 3 5 i- 0 0.5 I 1.5 2 2.5 3 35 rim lml Time [ms]

69

dam has more complicated I 1

d "6!5 0 0.5 1 1.5 2 2.5 1 35

Time lmsl

sum of two is good

3

2.5

2 -

n

U VI

5 1.5-

m .-

I 1 1 I I

-

Tail satisfies rate equation for self - recombination of quasiparticles

I I I I I 1

0.5 I 1.5 2 2.5 3 3.5 Time [ms]

Start satisfies equation for electrothermal relaxation

with time constant rerf

I ( t ) = I,, exp( -t I rev)

m 3

00 cc 2 n 0 c W

Counts per 2 eV bin

W cn

A P a 01

-. P CD 0

-.A

P CD UI

A VI 0 0

, A ul 0 VI

W pads

5.9 and CU Collimator

x-rays kev Fe- 55 source

38

7 - ?

0 7

X

aq - ?

0 ’ ..

2-g Y

E ‘ti= 0

T-7 - 0

X .-

c9 0

u?z $

‘ti=

0 Y

E 0

0

I

WE] JUeJJfl=) [due] iuaun=>

c9 0

a ' 9% O P

2 W

=P w- 3 9r)

I).

d W

250

200

k 150 d)

00

50

I 1 f

61

16 -4 -2 0 2 4 6 Delay X [psec]

1 2 ' 3 ' 4 5 6 7 0 0 -

X-Ray Energy [keV]

1

300

. 250.

3200. C

: 150.

100.

50.

0

4

7

- .

-

250 7

2 200

2 150. 100

E

5 0 .

0

*

300 250

250

22 c 200.

$150.

100

50

- '

d200. c

Energy Energy [keV]

E c 200 a 3 150.

100.

50

5 v

-

.

300.

250.

$200. E

;" 150 .

100.

5 0 .

0

6

300 300.

250 - 250

. E200' . E200' c

. $150. ' : 1 m

100. 100-

50 - 50 '

0 0 L

300

250

Energy [kev]

I

W/Al QET Sensors forCDMS

Photograph c of Phonon Sensor

Trapping Schematic Energetic

Quasi particles

Trapping Phonon Absorption Diffusion i h c i - I J O O L , '

;? ,.- ' ) i l 1 ' ) ! t i \ < , . ,

!

Quasiparticle Loss Measurement Test Structures (UCB & Stanford)

BondPad WTES AI Absorber

b i . 1 WIAI Trap \ / 1

\

2 0 pin I Si Substrate

0*45 t 0.4

0.35

>1 0.3

T0.25 2

P) 24

: 0.2 Lil L L & 0.15

0.1

0.05

0 50 Number

0.45

0.4

0.35 - c

0.3 24 L.

k W 0.15 a

0.1

0.05

I

I

1 4 0

0 0.1 0.2 0.3 0.4 A ETF Energy [keV]

44

1 I I Y

I O ' loo t

IO"1 1 o 3 1 0" 10 '

Temperature [ K]

I*+

Ionization + Phonon Readout I

-- .>

> .- P I & - 3~'iisw-s plus ionizatk::?

~ - ~ - ~- - - ~ _ _

100 g Si Crystal 1 cmThick 3" Diameter - --

0 Imaging Capability -I At=25ps across 3" -

Muon Veto =: 100 p s

lOnlzalbn and Phonon Evm( m 100 g Si Detector 700,

Ionization 6 o o L signal defines

\tart time 5 o o c

200 - 1

100 - A -4 * 0 -

-100 I

-30 -20 -10 0 10 20 30 40 50 Bo 70 1

Time m1

i

X-Y Imaging with Phonons

-15 -10 -5 0 5 10 15 X Delay bs]

-15

blockcci iw

- .. . . . . . _ .

- . . .

15

10

5 - Ul %

x 3

m a B >

-5

-10

. . -10 -5 0 5 IO 15 -9

X Delay bsl

lcm lcm PhononSide

w* Charge Side

lead 241Am Sources

Above 70 keV

-10 -5 0 5 IO IS X Delay [PI

47

CDMS I - Stanford shallow site

Panama Street

100 g Si detector in CDMS Run 18

3

8 60- > 25 0

. . 5 4 0 . .

"0 20 40 60 80 100 Recoil [keV]

I 20 40 60 80 100

Recoil [keV]

. ' . 100- . . . . ,,. . ,' . . .. muon

~

"0 20 40 60 80 100

Two months of continuous

Recoil [keV]

! \ I P candidates ~ ( - ..I- :toed rieutrons iexpz:: -.

- hat, operation! ! ! -. 1 . ' l J L L c ~ distribution (t~x':: ~ - - -c,.

49

Phonon Risetime Information

Risetime Distribution from 6oCo

0' I 0 50 100 0 15 30

Phonon Sum [keV] Calibration data with % p s RT Cut

1 Electrons (low Q,lP)

80-

- 8 60- %

5 4 0 -

- C C

20

0" . 0 20 40 60 80 I 00 0 20 40 60 80 100

Recoil [ keV] Recoil [keVJ

FLIP fast phonon physics

Particle interactions creat e-h pairs Phonons generated - Plasma cloud (diffuse) - Drifting charge (ballistic) - Recombination (ballistic)

Phonon Sensors /

'.. Ionization Electrode

+ IVeV, Erecoil = P - N e V + 'recomb tot P = P p Lasma tot

51

Risetime Discrimination Shown Icebox Gamma set

'̂ i----

I . .t . . . . . .. . :... . . . , .: ~

,: 4

. ;. . ,;.' .: i

. :. . . . . . . . . . . ; . . ... ' > . . . / . . . . . . .

5 2

CDMS New Limit & Goals

.

C057 long 1 20K rqmat 150

0 50 100 Ftcimn Energy Eke4

Co57 long-1 20K rqmaf

I " " " ~ " "

Charge Energy [kevee]

GOkeV neut 1 20K rama!

1 - . - . . . .. .

50 100 Phonon Energy [kev

0 10 20 30 40 M 60 70 80 90 100 110 120 130 1 4 0 '50 Charge Energy[Kebee]

60 keV wut 1 first 20K everts

54

Summary

TES’s are progressing rapidly and have demonstrated excellent performance For optical photon detection - From IR (5 pm or 0.25 eV) to UV (350 nm or

4 eV) energy resolution is 4 . 1 5 eV FWHM - Immediate use for fast spectrophotometry - Rapid progress on arrays for space and ground

For x-ray spectroscopy - State-of-the-art is NIST AI/Ag bilayer with

- Immediately useful to characterize materials - Astrophysics x-ray spectroscopy from space

3.1 eV FWHM at I .5 keV and 7.1 eV at 6 keV

For Dark Matter searches - W/A1 QET fast athermal phonon sensors - Demonstrated imaging & discrimination - Scheduled for use in CDMS-II(42 detectors)

Much interesting phonon and quasiparticle physics still to understand!

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