Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

PIERS Online

Design of Two-band 150-220 GHz Superconducting Bolometric Detection Structure

D. Rauly, A. Monfardini, Angel Colín, Pascal Febvre

Published Jan 1, 2008• 3 citations
Publisher

Abstract

We propose a pixel design, aimed to be included in an array, receiving and de- tecting simultaneously two bands of the Cosmic Microwave Background (CMB). It is composed of a bowtie antenna, feeding a diplexer structure to separate the signal towards two bolomet- ric detectors at 150 and 220GHz. The diplexer makes use of difierential transmission lines of Coplanar Striplines (CPS) and Broadside Coupled Lines (BCL) types, for flltering and separation purposes. The antenna and diplexer are planned to be fabricated in a superconductive niobium thin fllm deposited on a Silicon substrate, while NbSi bolometers will lie on a SiN membrane. The device has been simulated by means of ADS (Agilent), CST Microwave Studio and HFSS (Ansoft) softwares. Final dimensions that take into account the kinetic inductance of the super- conducting lines are proposed. Promising computation results are found, with signal separation up to 20dB.

DOI
10.2529/piers071220141852

Related papers

Superconducting sub-millimeter diplexer suitable for pixel-size two-band bolometric detection

Philippe Camus, D. Rauly, O. Guillaudin +3 more

The design of a diplexer, coupled to a planar bowtie antenna for two-band Cosmic Microwave Background detection is proposed, using both HFSS™ and ADS™ softwares. The two photometric bands are centered on 150 GHz and 220 GHz respectively. The diplexer is composed of two three-elements distributed filtering circuits, taking into account the complex impedance of the antenna and the impedance of the two resistive loading bolometers. The distributed elements are transmission lines Coplanar Strip Lines (CPS) and Broadside Coupled Lines (BCL). Their balanced geometry matches to the differential signal delivered by the bow-tie antenna, avoiding the addition of a balun circuit. The envisaged technology for strips and antenna is superconducting niobium at a few 100mK on Si substrate. The overall size of the antenna/diplexer structure is around 2 mm2, allowing to consider it as a pixel suitable for integration in a bolometer array.

SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference (IMOC)•Jan 1, 2007•0 citations

A superconducting diplexer for cosmic microwave background experiments

Mohammad Madi, Michael Mattes, Juan Ramon Mosig +2 more

Cosmic microwave background (CMB) studies require observations in several frequency bands simultaneously. For example, the detection of clusters of remote galaxies can be performed by comparing CMB photon fluxes at different frequencies, using the spectral deformation of the Planck law, due to the Sunyaev–Zeldovich effect. We propose a single pixel design to receive and detect simultaneously two frequency bands of the (CMB), centered at 150 and 220 GHz. It is composed of a bow-tie antenna, sensitive to the polarization of the incident radiation, feeding a diplexer structure to separate the signal towards two kinetic inductance resonators associated respectively with the 130–170 and 200–270 GHz frequency bands. The diplexer makes use of 150 nm thick niobium-based superconducting transmission lines of the coplanar strip-lines (CPS) type, for filtering and separation purposes, deposited on a 30 μm thick quartz substrate. A new coplanar matching structure, taking into account the kinetic inductance of the superconducting films, is proposed and achieves a nearly perfect match over more than 25% of each frequency band, along with a signal separation ratio above 30 dB at both center frequencies. The size of a single pixel is 0.9 mm × 1.2 mm.

Superconductor Science and Technology•Dec 5, 2013•0 citations

Quasi-Lumped Coplanar Waveguide Diplexers for a Multichroic Polarimeter

Sirui Ren, Tian Xia, Shiling Yu +19 more

This article presents a multichroic Kinetic Inductance Bolometer (KIB) polarimeter that utilizes coplanar waveguide (CPW) diplexers. The CPW diplexers function as filters, providing two passbands centered at 220 GHz and 280 GHz. The high-quality-factor resonant units deliver excellent transmission and isolation characteristics. Additionally, the quasi-lumped-element resonator design enables a significant reduction in size compared to conventional microstrip diplexers. The entire polarimeter—comprising orthomode transducer (OMT) probes, diplexers, KIBs, and CPW feed lines—is integrated on a single plane, allowing for one-layer superconducting thin-film fabrication with a simplified process. The compact size, superior frequency response, and streamlined fabrication process make the proposed pixel scheme suitable for integrated array development.

IEEE Transactions on Applied Superconductivity•Dec 12, 2024•0 citations

Development of Superconducting Detectors for Measurements of Cosmic Microwave Background

K. Hattori, M. Hazumi, H. Ishino +11 more

We present our recent development of superconducting detectors for measurements of cosmic microwave background. We have fabricated antenna-coupled superconducting tunnel junctions (STJs). Two different types of STJs have been fabricated: the parallel-connected twin junction and the microstrip. Both types of STJs made of Nb and Al have successfully detected 80 GHz millimeter wave radiation with photon-assisted tunneling. We have also developed microwave kinetic inductance detectors (MKIDs). The MKIDs offer us high multiplexing factors with a single readout line using the frequency-domain readout. We have developed abosrption-type and transmission-type MKIDs whose resonators are formed with either coplanar waveguides (CPW) or microstrips. The quality factor of the CPW MKID made of Nb is measured to be about 105. The microstrip MKID is being developed for the multichroic measurements.

Physics Procedia•Jan 1, 2012•4 citations

A 220 GHz superconducting titanium transition edge sensor array developed for cosmic microwave background experiments

Qianghui Luo, Jiaqiang Zhong, Wei Miao +10 more

Abstract In this paper, we report on the design, fabrication, and characterization of a 220 GHz superconducting transition edge sensor (TES) array developed for ground-based cosmic microwave background (CMB) experiments. Unlike conventional TES arrays adopting thermometers made of bilayer superconducting films, the TES array has thermometers made of simpler single-layer titanium (Ti) film deposited on a suspended silicon nitride (SiN x ) membrane. The thermal weak link is realized by releasing the TES’s thermal island including the Ti thermometer by dry etching with xenon difluoride (XeF2), giving a typical thermal conductance of 25 pW K−1. Its thermal-conductance mechanism is further studied by fitting the measured TES’s complex impedance with a three-block thermal model. The dark and optical noise equivalent power (NEP) of a superconducting TES are both measured. Despite existing lens reflection and dielectric loss in the superconducting microstrip line, its typical optical NEP reaches 100 aW Hz−0.5, which meets the sensitivity requirement for ground-based CMB experiments.

Superconductor Science and Technology•Sep 6, 2023•10 citations

Superconducting Microwave Resonator Arrays for Submillimeter/Far-infrared Imaging

Omid Noroozian

Superconducting microwave resonators have the potential to revolutionize submillimeter and far-infrared astronomy, and with it our understanding of the universe. The field of low-temperature detector technology has reached a point where extremely sensitive devices like transition-edge sensors are now capable of detecting radiation limited by the background noise of the universe. However, the size of these detector arrays are limited to only a few thousand pixels. This is because of the cost and complexity of fabricating large-scale arrays of these detectors that can reach up to 10 lithographic levels on chip, and the complicated SQUID-based multiplexing circuitry and wiring for readout of each detector. In order to make substantial progress, next- generation ground-based telescopes such as CCAT or future space telescopes require focal planes with large-scale detector arrays of 104–106 pixels. Arrays using microwave kinetic inductance detectors (MKID) are a potential solution. These arrays can be easily made with a single layer of superconducting metal film deposited on a silicon substrate and pattered using conventional optical lithography. Furthermore, MKIDs are inherently multiplexable in the frequency domain, allowing ∼ 103 detectors to be read out using a single coaxial transmission line and cryogenic amplifier, drastically reducing cost and complexity. An MKID uses the change in the microwave surface impedance of a superconducting thin-film microresonator to detect photons. Absorption of photons in the superconductor breaks Cooper pairs into quasiparticles, changing the complex surface impedance, which results in a perturbation of resonator frequency and quality factor. For excitation and readout, the resonator is weakly coupled to a transmission line. The complex amplitude of a microwave probe signal tuned on-resonance and transmitted on the feedline past the resonator is perturbed as photons are absorbed in the superconductor. The perturbation can be detected using a cryogenic amplifier and subsequent homodyne mixing at room temperature. In an array of MKIDs, all the resonators are coupled to a shared feedline and are tuned to slightly different frequencies. They can be read out simultaneously using a comb of frequencies generated and measured using digital techniques. This thesis documents an effort to demonstrate the basic operation of ∼ 256 pixel arrays of lumped-element MKIDs made from superconducting TiNx on silicon. The resonators are designed and simulated for optimum operation. Various properties of the resonators and arrays are measured and compared to theoretical expectations. A particularly exciting observation is the extremely high quality factors (∼ 3 × 107) of our TiNx resonators which is essential for ultra-high sensitivity. The arrays are tightly packed both in space and in frequency which is desirable for larger full-size arrays. However, this can cause a serious problem in terms of microwave crosstalk between neighboring pixels. We show that by properly designing the resonator geometry, crosstalk can be eliminated; this is supported by our measurement results. We also tackle the problem of excess frequency noise in MKIDs. Intrinsic noise in the form of an excess resonance frequency jitter exists in planar superconducting resonators that are made on dielectric substrates. We conclusively show that this noise is due to fluctuations of the resonator capacitance. In turn, the capacitance fluctuations are thought to be driven by two-level system (TLS) fluctuators in a thin layer on the surface of the device. With a modified resonator design we demonstrate with measurements that this noise can be substantially reduced. An optimized version of this resonator was designed for the multiwavelength submillimeter kinetic inductance camera (MUSIC) instrument for the Caltech Submillimeter Observatory.

•Jun 12, 2012•11 citations
We propose a pixel design, aimed to be included in an array, receiving and de- tecting simultaneously two bands of the Cosmic Microwave Background (CMB). It is composed of a bowtie antenna, feeding a diplexer structure to separate the signal towards two bolomet- ric detectors at 150 and 220GHz. The diplexer makes use of difierential transmission lines of Coplanar Striplines (CPS) and Broadside Coupled Lines (BCL) types, for flltering and separation purposes. The antenna and diplexer are planned to be fabricated in a superconductive niobium thin fllm deposited on a Silicon substrate, while NbSi bolometers will lie on a SiN membrane. The device has been simulated by means of ADS (Agilent), CST Microwave Studio and HFSS (Ansoft) softwares. Final dimensions that take into account the kinetic inductance of the super- conducting lines are proposed. Promising computation results are found, with signal separation up to 20dB.
The design of a diplexer, coupled to a planar bowtie antenna for two-band Cosmic Microwave Background detection is proposed, using both HFSS™ and ADS™ softwares. The two photometric bands are centered on 150 GHz and 220 GHz respectively. The diplexer is composed of two three-elements distributed filtering circuits, taking into account the complex impedance of the antenna and the impedance of the two resistive loading bolometers. The distributed elements are transmission lines Coplanar Strip Lines (CPS) and Broadside Coupled Lines (BCL). Their balanced geometry matches to the differential signal delivered by the bow-tie antenna, avoiding the addition of a balun circuit. The envisaged technology for strips and antenna is superconducting niobium at a few 100mK on Si substrate. The overall size of the antenna/diplexer structure is around 2 mm2, allowing to consider it as a pixel suitable for integration in a bolometer array.
Cosmic microwave background (CMB) studies require observations in several frequency bands simultaneously. For example, the detection of clusters of remote galaxies can be performed by comparing CMB photon fluxes at different frequencies, using the spectral deformation of the Planck law, due to the Sunyaev–Zeldovich effect. We propose a single pixel design to receive and detect simultaneously two frequency bands of the (CMB), centered at 150 and 220 GHz. It is composed of a bow-tie antenna, sensitive to the polarization of the incident radiation, feeding a diplexer structure to separate the signal towards two kinetic inductance resonators associated respectively with the 130–170 and 200–270 GHz frequency bands. The diplexer makes use of 150 nm thick niobium-based superconducting transmission lines of the coplanar strip-lines (CPS) type, for filtering and separation purposes, deposited on a 30 μm thick quartz substrate. A new coplanar matching structure, taking into account the kinetic inductance of the superconducting films, is proposed and achieves a nearly perfect match over more than 25% of each frequency band, along with a signal separation ratio above 30 dB at both center frequencies. The size of a single pixel is 0.9 mm × 1.2 mm.
This article presents a multichroic Kinetic Inductance Bolometer (KIB) polarimeter that utilizes coplanar waveguide (CPW) diplexers. The CPW diplexers function as filters, providing two passbands centered at 220 GHz and 280 GHz. The high-quality-factor resonant units deliver excellent transmission and isolation characteristics. Additionally, the quasi-lumped-element resonator design enables a significant reduction in size compared to conventional microstrip diplexers. The entire polarimeter—comprising orthomode transducer (OMT) probes, diplexers, KIBs, and CPW feed lines—is integrated on a single plane, allowing for one-layer superconducting thin-film fabrication with a simplified process. The compact size, superior frequency response, and streamlined fabrication process make the proposed pixel scheme suitable for integrated array development.
We present our recent development of superconducting detectors for measurements of cosmic microwave background. We have fabricated antenna-coupled superconducting tunnel junctions (STJs). Two different types of STJs have been fabricated: the parallel-connected twin junction and the microstrip. Both types of STJs made of Nb and Al have successfully detected 80 GHz millimeter wave radiation with photon-assisted tunneling. We have also developed microwave kinetic inductance detectors (MKIDs). The MKIDs offer us high multiplexing factors with a single readout line using the frequency-domain readout. We have developed abosrption-type and transmission-type MKIDs whose resonators are formed with either coplanar waveguides (CPW) or microstrips. The quality factor of the CPW MKID made of Nb is measured to be about 105. The microstrip MKID is being developed for the multichroic measurements.
Abstract In this paper, we report on the design, fabrication, and characterization of a 220 GHz superconducting transition edge sensor (TES) array developed for ground-based cosmic microwave background (CMB) experiments. Unlike conventional TES arrays adopting thermometers made of bilayer superconducting films, the TES array has thermometers made of simpler single-layer titanium (Ti) film deposited on a suspended silicon nitride (SiN x ) membrane. The thermal weak link is realized by releasing the TES’s thermal island including the Ti thermometer by dry etching with xenon difluoride (XeF2), giving a typical thermal conductance of 25 pW K−1. Its thermal-conductance mechanism is further studied by fitting the measured TES’s complex impedance with a three-block thermal model. The dark and optical noise equivalent power (NEP) of a superconducting TES are both measured. Despite existing lens reflection and dielectric loss in the superconducting microstrip line, its typical optical NEP reaches 100 aW Hz−0.5, which meets the sensitivity requirement for ground-based CMB experiments.
Superconducting microwave resonators have the potential to revolutionize submillimeter and far-infrared astronomy, and with it our understanding of the universe. The field of low-temperature detector technology has reached a point where extremely sensitive devices like transition-edge sensors are now capable of detecting radiation limited by the background noise of the universe. However, the size of these detector arrays are limited to only a few thousand pixels. This is because of the cost and complexity of fabricating large-scale arrays of these detectors that can reach up to 10 lithographic levels on chip, and the complicated SQUID-based multiplexing circuitry and wiring for readout of each detector. In order to make substantial progress, next- generation ground-based telescopes such as CCAT or future space telescopes require focal planes with large-scale detector arrays of 104–106 pixels. Arrays using microwave kinetic inductance detectors (MKID) are a potential solution. These arrays can be easily made with a single layer of superconducting metal film deposited on a silicon substrate and pattered using conventional optical lithography. Furthermore, MKIDs are inherently multiplexable in the frequency domain, allowing ∼ 103 detectors to be read out using a single coaxial transmission line and cryogenic amplifier, drastically reducing cost and complexity. An MKID uses the change in the microwave surface impedance of a superconducting thin-film microresonator to detect photons. Absorption of photons in the superconductor breaks Cooper pairs into quasiparticles, changing the complex surface impedance, which results in a perturbation of resonator frequency and quality factor. For excitation and readout, the resonator is weakly coupled to a transmission line. The complex amplitude of a microwave probe signal tuned on-resonance and transmitted on the feedline past the resonator is perturbed as photons are absorbed in the superconductor. The perturbation can be detected using a cryogenic amplifier and subsequent homodyne mixing at room temperature. In an array of MKIDs, all the resonators are coupled to a shared feedline and are tuned to slightly different frequencies. They can be read out simultaneously using a comb of frequencies generated and measured using digital techniques. This thesis documents an effort to demonstrate the basic operation of ∼ 256 pixel arrays of lumped-element MKIDs made from superconducting TiNx on silicon. The resonators are designed and simulated for optimum operation. Various properties of the resonators and arrays are measured and compared to theoretical expectations. A particularly exciting observation is the extremely high quality factors (∼ 3 × 107) of our TiNx resonators which is essential for ultra-high sensitivity. The arrays are tightly packed both in space and in frequency which is desirable for larger full-size arrays. However, this can cause a serious problem in terms of microwave crosstalk between neighboring pixels. We show that by properly designing the resonator geometry, crosstalk can be eliminated; this is supported by our measurement results. We also tackle the problem of excess frequency noise in MKIDs. Intrinsic noise in the form of an excess resonance frequency jitter exists in planar superconducting resonators that are made on dielectric substrates. We conclusively show that this noise is due to fluctuations of the resonator capacitance. In turn, the capacitance fluctuations are thought to be driven by two-level system (TLS) fluctuators in a thin layer on the surface of the device. With a modified resonator design we demonstrate with measurements that this noise can be substantially reduced. An optimized version of this resonator was designed for the multiwavelength submillimeter kinetic inductance camera (MUSIC) instrument for the Caltech Submillimeter Observatory.