Development of NbTiN-Al MKID camera
for the Nobeyama 45-m telescope
T. Nitta
University of Tsukuba

Contents✴ Scientific Motivation✴ Microwave Kinetic Inductance Detector (MKID)✴ MKID Camera for the Nobeyama 45-m telescope✴ Results of Lab Measurements✴ Future Development✴ SummarySurvey of Distant Galaxies✴ Distant Galaxy Survey
distant galaxy is important source tounderstand the galaxy evolution
・Optical : absorbed by dust
・mm-wave to THz : dust emission- multi-band observation
・redshift can be determined from SED-©NASA✴ Star Formation History-distant galaxy is obscured by dust

-wide-filed mm & submm continuum
camera is important to survey galaxies
Casey et al., 2013

Wide-Field Observations✴ Multi-pixel camera for wide-field observations observation  area¯`{~ 2.5 m çzØ¬öþòýºè
optical  imageu±-ÝČýºæÆó_ã¤-ÊĎ

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Ivisonet al., 2000
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ALMA : high-angularresolution interferometer
Fig. 4 A schematic illustration of the 10 m THz
sĈð 5.8 m/s Î)Č10 m/s RIĈ→ follow-up
observationsof galaxies
detected by the cameraąĎ +(():G?vr2<telescope>B»ČTHz »á¾rIªĉ®T)ČÃ
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To observe a lot of distant galaxies,• camera development for wide-field observation• good observation site for astronomical observations
are importantCamera Development✴ 100-GHz band Camera
・Camera will be installed on the Nobeyama 45m telescope
・Collaboration with National Astronomical Observatory of Japan・free-free emission is dominant at the 100-GHz continuum− good tracer of the massive star forming region (HII region)
Observation Frequency
Field-of-viewDetector100-GHz band（90 − 110 GHz）
〜 3 arcmin
Microwave Kinetic Inductance Detector

No. of pixels

109 pixels

Bath temperature< 200 mK

✴ THz band Camera (Future Plan)
・Our group is planning to construct the 1deg. FoV 10 m telescope at the Antarctica plateau.
・Target bands : 400 / 850 / 1300 GHz

MKID is one of the important technology for realizing wide-field camera

Microwave Kinetic Inductance Detector (MKID)✴ Operation Principle

Day et al., Nature, 2003
MW Readout(3 - 9GHz)
図 2.2:(左)MKID (右)MKID の等価回路

・Superconducting resonators operated in
the microwave range
最初に述べたように MKID とはマイクロ波帯で動作す
photonequilibrium
・Incident photons break Cooper-pair から分かるようにキャパシタンスとインダクタンスが並
absorption→ Kinetic Inductance is changed
MKID では共振器の長さは読み出しに使用するマイクロ→ Resonance frequency of MKID is also
長になっており、片側 short , もう片側が open になっていchanged
ω0 はクロ波で共振を起こす。この時、共振周波数
δf500 umex) Al MKID : > 85 GHz photons can be observed Gold：Superconductor(Al)Black：Substrate (Si)

✴ Advantage of MKID

2π
ω0 = !
4l (Lg + Lk )C・High-detector yield is expected because
the MKID fabrication
process is relativelysimpleで表される。ここで、l は共振器の長さ、Lg , C
は超伝導MKIDにEのエネルギーをパシタンスである。
・Intrinsic frequency multiplexing capability→ ~1000 pixels
can bemeasured
one LNAgap ＜ hν with46を破壊すると力学インダクタンスが変化することから、
→
2GHz/
2MHz
span〜
1000素子程度
MKID2
MKID1
MKID3
MKID1 MKID2 MKID3

Readout

S21 [dB]

44424038

2πω0 − ∆ω0 = !
4l (Lg + Lk + ∆36
Low-noiseampliﬁer2.3 に示すように低周波側にシフトする。となり、図6.376 6.378
6.38
6.382 6.384 6.386 6.388
6.39
Frequency [GHz]Test Observations✴ Commissioning in 2018 season
・Optics, detector yield and stability satisfy a requirement

BAD ・Measured
A sensitivity
D wasDoneDorder lower than thetarget sensitivity.
 Evaluation of LeKID array for the Nobeyama 45-m telescope Comparison between LeKID and Antenna-coupled KID

Antenna-coupled KID（developed by U. of Tsukuba）
velopedby French NIKA2group） sensitivityof camera✴ Improvement

planar antenna

1. Low optical efficiency of MKID array

・All Al MKID (gap E of Al : ~85 GHz)
- Loss at GND & antenna ( = low efficiency)・NbTiN-Al MKID (gap E of NbTiN : ~1.1 THz)
- NbTiN GND and Al signal line
Yates et al., 2011
from prof.2.A. Surface
Monfordinireflection
and prof. J. ofMacias-Perez
Si lenses

Al-MKIDSignal
GND
GND(Al) Al (Al)readout line・highbyrefractive
index causes
reflections of ~30% at lens surface
was developed
NIKA2 camera
group

coplanar waveguideFocal Plane Array✴100-GHz band MKID Camera< NbTiN-Al MKID >・Double-slot antenna & Si lens array
・Glass beads AR coating✴109 pixel NbTiN-Al MKID Array
・200 nm NbTiN & 50 nm Al
・MKIDs are distributed over the entire
3-inch Si wafer
AR Coating

Si Lens Array
3 inch Si Wafer
Superconducting film (MKID + antenna)~75 mmfabricated by Y. Murayama

Reflectan

Depth

Author Proo300

Anti-Reflective Structures
200
10001

✴ Subwavelength Structure (SWS)

1.5

2

2.5

3

3.5

1

0.1

0.01

0

0.05

0.1

Effective Refractive Index

0Fre

・Periodic structures inFig.
subwavelengthscaleeffective refractive index of the three types of pyramid3 (Left) Calculated
depth. Black, (AR)red andlayersblue lines correspond to the reference shape, pyram
・The structures act asofantireflective
and 35-µm-radius curved bottom, respectively. d = 0 µm and 600 µm are b→ ex) optimized forthe
Si pyramid-type: n = 1.84 structures, respectively (see Fig. 2). (Right) Calculated refle=1period
width

Effective Layer (1 < n < 3.4)
Silicon (n ~ 3.4)

Single Layer✴ Fabrication Method
・Development of a dedicated three-axis
dicing machine(Oshima Prototype Engineering Co.)
→Lens surface can be machined
・Various (Rectangular and V-shape) typesof dicing blades were usedSilicon (n ~ 3.4)

tednairpyramid-type structures using HFSS [29]. The result of a plain flat silicon is aIncidentwave
SWS
higher-orderdiffraction
occurs at the nfrequency
air = 1 above 330 GHz (Color figure oNitta et al., 2018

Lab Measurement✴ Optical Measurement❖ Detector Yield❖ Frequency Response❖ Beam Patterns✴ Camera Sensitivity❖ Optical Efficiency❖ Noise Equivalent Power
Measured with
Makoto Nagai (NAOJ), Yosuke Murayama (D3), Ryuji Suzuki,Ryotaro Hikawa, Rikako Suzuki (M2) and many collaborators

受信帯域測定
受信帯域測定ΑΔप೾਺ಛੑͷଌఆ22ϑʔϦΤ෼ޫ‫ʹث‬ΑΔप೾਺ಛੑͷଌఆୈୈ
3 3ষষ ϑʔϦΤ෼ޫ‫ʹث‬ΑΔप೾਺ಛੑͷଌఆ

フーリエ分光器による帯域測定4
測定フーリエ分光器による帯域測定

44

22
22

Frequency
Band
Characteristic
・フーリエ分光器（FTS）を⽤いて，カメラの周波数特性を測定
ද3.3:
3.3: FTS
FTS ͷઃఆ
ͷઃఆද

ද 3.3: FTS ͷઃఆ・フーリエ分光器（FTS）を⽤いて，カメラの周波数特性を測定 ୯Ґ
୯Ґ

み出し回路

mmBoxcarResponseResponse)*+ [Hz]Intensity

beam splitterbeam splitter

fixed mirror
fixed mirror

IFIFONON

1.0
1.0
2.00
2.00

カメラのカメラのReadout Circuit
周波数特性⼲渉信号周波数特性)*)*[Hz]+ +[Hz]moving mirror
movingmirrorΞϙλΠθʔγϣϯ

2.00

Frequency
FrequencyΞϙλΠθʔγϣϯ Boxcar
読み出し回路ΞϙλΠθʔγϣϯ Boxcar
読み出し回路周波数
lightsource
1.0周波数
lightsourceΞύʔνϟʔ

Normalized ResponseήΠϯFrequency%E2 [dB]

放射強度
放射強度

✴ Fourier Transform Spectrometerճ22ճ
−10.50,0.25 cm
cm−10.50,
0.25
信号の強度変化とMKIDの応答
信号の強度変化とMKIDの応答
4.00mm/sec
4.00mm/sec%%E2[dB]
E2[dB]

メラの周波数特性を測定
定߲໨߲໨‫͔ݯ‬ΒͷೖࣹޫΛϏʔϜεϓϦολʹΑͬͯ൓ࣹޫͱ
͔ΒͷೖࣹޫΛϏʔϜεϓϦολʹΑͬͯ൓ࣹޫͱ
・周波数分解能4.6GHzでGHzで4.84.8THzまで測定THzまで測定 ੵࢉճ਺߲໨
୯Ґ
・周波数分解能4.6ੵࢉճ਺ʔͰ൓ࣹͤ͞ɼ‫ݩ‬ͷޫ࿏ʹ໭͠ϏʔϜεϓϦολͰॏͰ൓ࣹͤ͞ɼ‫ݩ‬ͷޫ࿏ʹ໭͠ϏʔϜεϓϦολͰॏ෼ղೳ
ੵࢉճ਺
2ճ෼ղೳ
FTSによるデータ取得の流れ‫ڸ‬ɼ΋͏ยํΛޫ࣠ํ޲ʹҠಈͤ͞Δ͜ͱͰɼ2ͭͷ
FTSによるデータ取得の流れ−12 ͭͷɼ΋͏ยํΛޫ࣠ํ޲ʹҠಈͤ͞Δ͜ͱͰɼεΩϟϯεϐʔυεΩϟϯεϐʔυ෼ղೳ
0.50,0.25cm
信号の強度変化とMKIDの応答มԽʢΠϯλʔϑΣϩάϥϜʣΛಘΔɽޫ‫ݯ‬Λ୯৭ޫԽʢΠϯλʔϑΣϩάϥϜʣΛಘΔɽޫ‫ݯ‬Λ୯৭ޫଐੑଐੑεΩϟϯεϐʔυ
4.00mm/sec
光源
光源‫ظ‬ͷࡾ֯ؔ਺ͱͳΔ[32]ɽಘΒΕͨΠϯλʔϑΣϩάθϩϑΟϦϯά
Sourceͷࡾ֯ؔ਺ͱͳΔ[32]ɽಘΒΕͨΠϯλʔϑΣϩάθϩϑΟϦϯάଐੑIFήΠϯԠͨ͠εϖΫτϧ͕ಘΒΕΔɽήΠϯͨ͠εϖΫτϧ͕ಘΒΕΔɽ
(MercuryLamp)Ξύʔνϟʔ
θϩϑΟϦϯά
ONΞύʔνϟʔ

mmmm

⼲渉信号
⼲渉信号

Frequency [GHz]ཧਤ [32]ɽޫ‫͔ݯ‬Βೖࣹͨ͠ޫ͕‫ݻ‬ఆ‫ͱڸ‬time [s]ਤ [32]ɽޫ‫͔ݯ‬Βೖࣹͨ͠ޫ͕‫ݻ‬ఆ‫ͱڸ‬time [s](a) αϯϓϦϯάϨʔτ 26 [S/s](b) energyαϯϓϦϯάϨʔτ
28 [S/s]Al
gapfiltercutoffͬͯੜͨ͡ޫ࿏ࠩʹΑͬͯ‫ׯ‬ব৴߸ΛಘΔ(a) αϯϓϦϯάϨʔτ 26 [S/s](b) αϯϓϦϯάϨʔτ 28 [S/s]ͯੜͨ͡ޫ࿏ࠩʹΑͬͯ‫ׯ‬ব৴߸ΛಘΔ
ਤ 3.11: औಘͨ͠‫ׯ‬ব৴߸͔ΒҠಈ‫ڸ‬ͷยಓ෼Λ੾Γऔͬͨਤɽ࣌ؒʹର͢Δ෼ղೳ͸ಡΈग़͠ճ

カメラの周波数特性

ਤ 3.11: औಘͨ͠‫ׯ‬ব৴߸͔ΒҠಈ‫ڸ‬ͷยಓ෼Λ੾Γऔͬͨਤɽ࣌ؒʹର͢Δ෼ղೳ͸ಡΈग़͠ճ
Frequency
フーリエ変換࿏ʹΑΔ‫ৼڞ‬प೾਺ͷαϯϓϦϯάϨʔτʹΑܾͬͯ·ΔɽTime࿏ʹΑΔ‫ৼڞ‬प೾਺ͷαϯϓϦϯάϨʔτʹΑܾͬͯ·Δɽ

Frequency

フーリエ変換・The measured center frequency
andtime[s]bandwidth are 95 GHz and 16 GHz, respectively.
68༻͍ͨଌఆ‫ܥ‬ϯάϨʔτ
2[S/s](b)αϯϓϦϯάϨʔτ
2[S/s]
3.6Χϝϥͷप೾਺ಛੑ・This
resultisingoodagreement
withtheexpected response which is determined by the Al͍ͨଌఆ‫ܥ‬
3.6 Χϝϥͷप೾਺ಛੑ৴߸͔ΒҠಈ‫ڸ‬ͷยಓ෼Λ੾Γऔͬͨਤɽ࣌ؒʹର͢Δ෼ղೳ͸ಡΈग़͠ճsuperconducting
gap
the 120-GHz low-pass filter used in the cold optics.
࿏ FSP4000
ʢਤ 3.4ʣΛ༻͍ͯߦͳͬͨɽͳ͓ɼຊΧ
3.6.1andϑʔϦΤม‫׵‬Beam Characteristic✴ Knife-Edge Measurement

Arnaud et al., 1971

・Scan thin blackbody (BB) source at a constant speed-Result(1/3)
300 K and Li-N2 (77 K) BB sources were used to obtain theResult (Optical Response, B

Result(1/3)

optical response

Result (OpticalResponse,Beam-shape)・Differential
responses correspondØ Difference of () betweento the beam shapesØDifferen

Beam map (shapeandloadposition)
can beload
obtained
hot&coldØ Difference of () betweenØDifferential response(Be< Raw Data >< Differential Response>
hot load & cold load
For MKID20-Coldload⇨
77 K loadcross section

thin BBload⇨source (300 K)
Cold

For MKID20

Differentiate

Differentiate

BB in Li-N2 (77K)

300K load⇨
load
Hot25 mm/s
Top View

Hot load⇨

Knife-edge

ü For each KID, the timin⇨ The peak position o⇨ planeWe obtain
where・Beam waist size at the camera focal
is almostthe eaüsame
For
KID, the timingof thechangeof (ü FromHPBW,we obtain
2020/3/3
Historyof Universeseminaraseachthe simulation.

Future Plan

0 BAD A

LeKID Array

DDD

KineticInductance
Detector(LeKID)✴ Lumped Element2
D 45-m( 3 telescope D
Evaluation of LeKID array for the Nobeyama
・ Collaboration
with Université
Grenoble
Alpesand Antenna-coupled Comparison
between
LeKID
LEKID KID

Antenna-coupled KID（developed by U. of Tsu
S21[dB]

LeKID（developed by French NIKA2 group）

Jyunpei Takahashi, 2020

Frequency[MHz]・ 138 / 144 pixels : high yield

2 Dfrom prof. A. Monfordini and prof. J. Macias-Perez

Design( pixel4Yield

Jyunpei Takahashi, 2020
numberAntenna-coupled
KID
144AtmS21[dB]•❖ ThisThisarray
arraywaswasdeveloped
NIKA2camera
group
developed
by by
NIKA2camera
group
Measurement
13895.8%• fabricated by
U. of Tsukuba
NIKA2 : Adam et al., A&A 609, A115, 2018
NIKA2 : Adam et al., A&A 609, A115, 2018
• 109 pixel• 144 pixel array・Detector
yieldarrayis almost the same beLeKID hybrid KIDpixel(Tiarray• Al-NbTiN•❖ 144bi-layerand Al) for changing Tc and tuning theYates et al., APL, 99, 0735
Catalano etA&A580, A15,
observationband❖ bi-layer(Ti andAl) for changing
Tcal.,andtuning
the 2015

observation band

Temperature[K]Summary✴ Scientific Motivation
・distant galaxy survey- wide-field survey is important to detect the unknown galaxies✴ MKID Camera for the Nobeyama 45-m Telescope
・MKID is the superconducting resonator operated in the microwave range
・Camera development- 109 pixel array using lens-antenna coupled NbTiN-Al MKIDs- Results of beam pattern, yield and frequency response are as expected.
- This camera will be installed on the Nobeyama 45-m telescope in this Oct.
- improvement of the multi-pixel readout system is needed✴ Future Development
・Collaboration with Université Grenoble Alpes (LeKID development)
・~ 20000 pixel camera is designed for the Antarctica 10 m telescope