Transcript TES - INRiM
Mauro Rajteri
Divisione OTTICA
Photon
: also called
Light Quantum
, minute energy packet of electromagnetic radiation. The concept originated (1905) in Einstein’s explanation of the photoelectric effect (enc. Brittanica)
Photon counting:
average count rate intensity of the light beam but actual count rate fluctuates from measurement to measurement.
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Coherent light & constant intensity:
3.1
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"Classical" Single photon detector Photon source Photon number resolving (PNR) detector Mauro Rajteri, 12/06/2013 Panoramica INRIM 6/46
TES:
a superconducting film operated in the temperature region between the normal and the superconducting state
D
T c
~ 1 mK high sensitive thermometer
t
( s )
R I
bias
I tes
Workig Point
T c
~ 100 mK
T R
bias <<
R
tes D
T
D
R @ Voltage bias
D
I
I
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TES:
a superconducting film operated in the temperature region between the normal and the superconducting state
D
T c
~ 1 mK high sensitive thermometer
t
( s )
R I
bias
1 ph
I tes
Workig Point
T c
~ 100 mK
T R
bias <<
R
tes D
T
D
R @ Voltage bias
D
I
I
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TES:
a superconducting film operated in the temperature region between the normal and the superconducting state
D
T c
~ 1 mK high sensitive thermometer
R
2 phs
I
bias
I tes
Working Point
T c
~ 100 mK
T R
bias <<
R
tes D
T
D
R @ Voltage bias
D
I
I t
( s ) Mauro Rajteri, 12/06/2013 Panoramica INRIM 9/46
Bilayer – proximity effect Ti=24 nm, Au=54 nm
10 µm X10 µm 20 µm X 20 µm
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T
c
∆T
c
R
n =121 mK = 2 mK = 0.220 Ω 10/46
P s P e P inc Superconductor - e g e-ph Superconductor - ph g ph-sub Substrate g sub-b Thermal bath T e T ph T sub g = thermal conductance
P s
K
(
T n
n T sub
)
K
= constant: material and geometry dependent
n
= constant: depends on the dominant thermal coupling mechanism T b For T < 1K electron-phonon decoupling
n
5 Mauro Rajteri, 12/06/2013 Panoramica INRIM 11/46
D
E FWHM
2 .
355 4
k
B
T c E sat n
2
E sat
CT c
Intrinsic Energy Resolution
∆E FWHM
is proportional to the operating temperature T
c
etf
th
1
n
1
T s n T c n
1
Effective TES response time
etf
is lower than
th
if
/n >1
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2w 0 z ~ 125 m 2 w (TES 20 x 20 m) acc
~
58%
@1.55
m ÷
80%
@1.3
m Gaussian beam: w 0 =4.7/5.6
l
=1.3/1.55
m @
m
0,5 mm 1,5 mm 0,25 1mm Cu bracket 3 mm 0.8 mm Silicon Mauro Rajteri, 12/06/2013 Panoramica INRIM 13/46
Optical coupling fiber-TES Reflection and transmission of superconducting film Antireflection coating or optical cavity a-Si 3 N 4 :Hy (low reflection index)
R(1550)=0.018%
a-SiH (high reflection index) Mauro Rajteri, 12/06/2013 Panoramica INRIM 14/46
Laser Attenuator Optical fiber INRIM: TES module D I TES Electronics & data aquisition SQUID current sensors (PTB) Mauro Rajteri, 12/06/2013 Panoramica INRIM 15/46
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2000 1800 1600 1400 1200 1000 800 600 400 200 0 0 1 10
Noisy
: Δ
E
= 0.46 eV 2 20 3 4 30 amplitude [mV] 40 5 50 histogram noisy fit (a) 60 D. Alberto, et al,
Optical Transition-Edge Sensors Single Photon Pulse Analysis
, IEEE Trans. Appl. Supercond.,
21
, 285 – 288 (2011) 3000 2500 2000 1500 1000 500 0 0
Wiener filter: 2x improvement on
D
E
10
Wiener
: Δ
E
= 0.22 eV histogram Wiener fit (b) 20 30 amplitude [mV] 40 50 60 Mauro Rajteri, 12/06/2013 Panoramica INRIM 18/46
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phs
20X20 μ m 2 l =1570 nm L. Lolli, et al.
J. Low Temp. Phys.
, vol. 167, pp. 803-808, 2012.
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Klyshko
Detector to be Calibrated w
s
N 1 = 1 N
COUNTER
N 1
COINC COUNTER
N C N 2 = 2 N 1 =N C / N 2 N C = 1 2 N w
p
N
Absolute Quantum Efficiency PARAMETRIC CRYSTAL
w
i
“Herald” Detector N 2
COUNTER Drawback: Klyshko's technique is not able to exploit the PNR ability of the detector Proposal and demonstration of an absolute technique for measuring quantum efficiency, based on an heralded single photon source , but exploiting the PNR ability of the detector
A. Avella et al OPTICS EXPRESS 2011
19
p. 23249-23257 Mauro Rajteri, 12/06/2013 Panoramica INRIM 21/46
P H
(
i
)
P A
(
i
)
Probability of observing
i
photons per heralding count in the presence of the heralded photon Probability of observing
i
photons per heralding count in the absence of the heralded photon (i.e. of observing
i
“accidental” counts) The probability of observing
0
photons per heralding count :
P H
( 0 ) ( 1 )
P A
( 0 ) ( 1 )
P A
( 0 ) Non detection & No accidental False her.& No accidental
“Total” Quantum Efficiency of the PNR detector
optical and coupling losses
detector proper Quantum Efficiency
Probability of having a True Heralding Count (not due to stray-light or dark counts)
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The probability of observing
i
photons per heralding count
P H
(
i
) [( 1 )
P A
(
i
)
P A
(
i
1 )] ( 1 )
P A
(
i
)
From each
P H
(
i
)
a value of “Total” Quantum Efficiency can be estimated
Consistency Test
From the probability of
0
0
P A
( 0 )
P H P A
( 0 ) ( 0 )
From the probability of
i
i
P H
[
P A
(
i
(
i
) 1 )
P A
(
i P A
) (
i
)] Mauro Rajteri, 12/06/2013 Panoramica INRIM 23/46
PDC single photon source
Pump source HWP NLC TES detection system
b a
IF2 IF1 Mauro Rajteri, 12/06/2013 Panoramica INRIM 24/46
PUMP DET1 total quantum efficiency
6 Repeated measurements each 5 hr. long >5 10 6 counts
Heralded Accidental
@ 807 nm prob.
of true heralding counts Mauro Rajteri, 12/06/2013 Panoramica INRIM 25/46
POVM provides the description of the measurement process “
n
” Prob. of output “
n
” Mauro Rajteri, 12/06/2013 Panoramica INRIM 26/46
POVM provides the description of the measurement process “
n
” Prob. of output “
n
” Mauro Rajteri, 12/06/2013 Panoramica INRIM 27/46
POVM provides the description of the measurement process “
n
” Prob. of output “
n
” : Prob. of having output “
n
” with m photons as input Mauro Rajteri, 12/06/2013 Panoramica INRIM 28/46
Simplest Solution:
Fock state source
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Simplest Solution:
Fock state source
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Simplest Solution:
Fock state source
Affordable Solution:
Coherent source
[Lundeen et al., Nat. Phys
5
, 27 (2009)] Mauro Rajteri, 12/06/2013 Panoramica INRIM 31/46
Coherent source
Pulsed laser source Experiment with a TES
1570 nm
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Coherent source
Pulsed laser source Experiment with a TES Mauro Rajteri, 12/06/2013 Panoramica INRIM 33/46
Coherent source
Pulsed laser source Experiment with a TES Mauro Rajteri, 12/06/2013 Panoramica INRIM 34/46
Coherent source
Linear detection model =5.1% G. Brida et al New Journal of Physics 14 (2012) 085001 35/46
Joint Projects for the exchange of researchers within the Executive Programme Italy-Japan 2010-2012
Alignment: ADR cold finger
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TiAu TES
T c
=301 mK
73
phs
l =1535 nm QE 50 %
@ 500 kHz means 3.65x10
6
photons/s (
473 fW
)
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R n
=0.45 45nm Au+45nm Ti 10 m x 10 m
T c
=106 mK
C e
=0.35fJ/K Mauro Rajteri, 12/06/2013 Panoramica INRIM
R
(
T
,
I
)
R n
2 1 tanh
T
T c D
I
L I
C e T
I
bias IR
2
R s
(
T I
,
R I
)
p
k R s
(
T
n
T s n
)
R
(
T
,
I
)
G
nkT c n
1 23 44 pW/K 40/46
eff
= 3.8
s
D
E
= (0.113 ± 0.001) eV
D
E
2 2 ln 2 1
E
x
2
x
1 (Submitted to APL) Mauro Rajteri, 12/06/2013 Panoramica INRIM 41/46
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TES
Photon number resolving detectors Wavelength range: UV-IR Quantum efficiency:50% 90% Dark counts: background limited Count rate:
1 MHz Working temperature: < 1K Mauro Rajteri, 12/06/2013 Panoramica INRIM 43/46
Sviluppo
Fabbricazione: C. Portesi, E. Monticone Caratterizzazione : E. Taralli, L.Lolli , E. Monticone, M. Rajteri (criogenica, elettrica e ottica) E. Taralli, L. Callegaro (impedenza)
Taratura Applicazioni
Ottica quantistica: A. Avella,G. Brida, L. Ciavarella, I. Degiovanni, M. Genovese, M. Gramegna, M.G. Mingolla,F. Piacentini, M.L. Rastello, P. Traina
Collaborazioni
J. Beyer, D. Fukuda, T. Numata, M.G.A. Paris, M. White, G. Cantatore, G. Ventura Mauro Rajteri, 12/06/2013 Panoramica INRIM 44/46
2001-2004 -Fotorivelatori superconduttivi ad elettroni caldi per il VIS-IR -Realizzazione di STJ come rivelatori in regime di conteggio di fotoni per applicazioni astrofisiche
E45 (2006-2010)
Rivelatori superconduttivi a transizione di fase per conteggio di singoli fotoni Quantum Candela
(2008-2011) Progetto premiale P5 (2012-2013)
Oltre I limiti classici della misura
NEW08 MetNEMS (2012-2015)
Metrology with/for NEMS
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