Advances in Far-Infrared Detector Technology. Jonas Zmuidzinas Caltech/JPL

Transcription

1 Advances in Far-Infrared Detector Technology Jonas Zmuidzinas Caltech/JPL December 1, 2016

2 OST vs Herschel: ~x gain from aperture Remaining gain from lower background with 4K telescope 2

3 OST vs Herschel: Detectors Herschel used arrays of a few hundred to a few thousand of detectors, and warm telescope, but had very high science return PACS blue channel (90 µm) 32 x 64 pixels 8 subarrays, 16x16 ea. Silicon bolometers CMOS mux TiN absorber Herschel/SPIRE Ge bolometers Herschel/PACS Si bolometers Origins Space Telescope will require: background-limited imaging & spectroscopy on a ~4 K space telescope 0 to 00x more detectors 0 to 00x better detector sensitivity Superconducting detectors are poised to meet this challenge #1 technology priority for OST (Staguhn, 1/3/17 presentation) 3

4 SCUBA 2: superconducting TES bolometers with 32:1 multiplexed SQUID readout no horns 5120 pixels per band, 0 mk, TES/SQUID TDM NEP ~ low -16 W Hz-1/2 Holland et al. 2013

5 MAKO: 484-pixel, 350 µm kinetic inductance detector array (00:1 mux density) 5

6 Basic Concept 6

7 CSO Deployment Attila Pradeep Bhupathi Attila Chris McKenney Kovacs Chris 7

8 MAKO at the CSO Sgr B2 Moon 8

9 Backgrounds for Cold Space Telescope OST requirements: NEP ~ few x -19 (imaging) NEP ~ few x -20 (spectroscopy) Imaging Dispersed spectroscopy Credit: J. Glenn 9

10 SAFARI TES detectors (SRON, Cambridge et al.) NEP ~ 2 x -19 W/Hz 1/2 Khosropanah et al pixel multiplexing Hijmering et al. 2016

11 SPACEKIDs: SRON, Cardiff et al. (Baselmans et al. 2016) NEP ~ 3 x -19 W / Hz-1/2 Array size and mux factor: 961 Pixel pitch: 1 mm Pixel yield: 85% Optical efficiency: > 50% Optical bandwidth: 1 octave Dynamic range: > 00 Electrical bandwidth: > 0 Hz Electrical crosstalk: < -30 db Cosmic ray deadtime: ~20% (improvements underway) 11

12 QCD: The Quantum Capacitance Detector R(V) Vg(V) Credit: P. Echternach / JPL

13 QCD: Far-infrared photon counting 500 us Photon Photon Photon Sweep rate ~ 22kHz spanning 4 Quantum Capacitance Peaks => effective sweep rate ~ 88kHz Should block background tunneling while still allowing tunneling due to single photon absorption Raw QC time trace should be absolutely periodic Gaps are due to high tunneling suppressing the Quantum Capacitance signal, due to photon absorption. Photon counting not required for OST science, but does offer some system-level advantages: *1/f noise not an issue, * low NEP strictly speaking not required. Credit: M. Bradford, P. Echternach 13

14 Detectors: OST s #1 Technology Challenge 14

15 SUMMARY OST s detector technology challenges: Scalability to detector counts > 5 NEP in the -19 to -20 W Hz -1/2 range These requirements have been demonstrated individually Very good prospects for meeting all simultaneously through some combination of concepts explored to date Will require focused R&D program 15

16 BACKUP CHARTS 16

17 Small-volume absorber-coupled KIDs Meandered Inductor Coupling Capacitor Interdigitated Capacitor Detector pitch: 1 mm Why this architecture? Low volume inductors ² Width: 150 nm ² Thickness: 20 nm ² Al: low resistivity è Good optical absorption with a low absorber volume ² Lens coupling è Minimize inductor area, allow for IDCs Low f0: few x 0 MHz τqp ~ 1 ms for Al Challenge: High yield? Microlens Array JPL / CIT / U. Colorado J. Glenn+ SPIE 2016

18 Follow-on project: ICarIS Balloon payload, proposed to NASA C + at µm z = U. Penn: Aguirre, Devlin (integration, gondola) JPL/CIT: Bradford, Hailey- Dunsheath (detectors - low-volume Al KIDs) U. Arizona: Marrone (telescope) Illinois: Vieira (optics) Chicago: Shirokoff (detector testing) ASU: Groppi, Mauskopf (readouts, machining) 18

19 0 Photon1noise$limited$sensi,vity$in$MKIDs$at$250$μm$ in'development'for'blast6tng,'a'balloon6borne'polarimeter' detector$development$is$a$collabora,on$between$nist,$upenn,$asu$and$stanford$ Feedhorn1coupled$ MKID$concept$ a)# a)# b)# NEPmea NEPphoton (Hz 1) f/f S fo (MHz) NEP (W/ Hz) wave0# guide# pW 20pW Power (pw) dual1polariza,on$sensi,vity$ within$one$spa,al$pixel$ c)# 19 TiN# b)# 16 1pW b)# c)# feedhorn$array$ 16 feedhorn# 5 Frequency (Hz) #mm# Power (pw) detector$chip$ 1 16 NEP NEP c)# 17 NEPmea NEP f/f S ) S δf/f (Hz NEP (W/ Hz) fo (MHz) 1 (Hz ) NEP (W/ Hz) photon pW pW 7pW 200#μm# 2 Sensi,vity$to$variable$temperature$thermal$load$ pixels Experimental$package$ 20pW 5 20 (pw) Power Frequency (Hz) (a) pW Power (pw) 16 photon photon$noise$ limited$ above$1pw$ photon$noise$$ predic,on$ 20pW 20 mea Frequency (Hz) (b) McKenney SPIE 2016; Hubmayr+ 1 0 Power (pw) 2014 (c) 1 2

20 2G array layout 468 pixel array Gold for thermalization Holes for pin alignment to microlens array Hexagonal lattice aligns with microlens array on back side of 20

21 TiN 3G: Dual Polarization 21