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Multi-color narrow-band Salisbury Screen and Jaumann Absorbers combined with optimized thick Si₃N₄ support layers are designed for wavelength selectivity in 7~14µm wavelength band. The Jaumann Absorbers are adopted as a vertically ‘stacked’ pixel structure to save space and enhance resolution compared against ‘tiled’ structure (pixels lying in a common plane).

The main purpose of the Cryogenic Underground Observatory for Rare Events (CUORE) experiment is the search for the Neutrinoless Double Beta Decay (0νDBD) of ¹³⁰Te reaching a sensitivity on Majorana mass better than 50 meV. Cuoricino represents not only the first stage of CUORE, but also the most massive 0νDBD experiment presently running. Present results and future planning of these experiments will be described in the paper.

The Superconducting Quantum Interference Device (SQUID) has been used and proposed often to read out low-temperature detectors for astronomical instruments. A multiplexed SQUID readout for currently envisioned astronomical detector arrays, which will have tens of thousands of pixels, is still challenging with the present technology. We present a new, advanced multiplexing concept and its prototype development that will allow for the readout of 1,000–10,000 detectors with only three pairs of wires and a single microwave coaxial cable.

The review describes the noise properties of the high temperature superconducting (HTS) bolometers developed for the applications in the optical electronic devices of infrared and submillimeter wave-lengths. The principle of high-T_c transition edge bolometer operation and bolometer noise theory are considered, taking into account the peculiarities of constant bias current and constant bias voltage modes. The published results of bolometer noise modeling are discussed. Various sources of the excess 1/f-noise in HTS films as temperature sensitive element for bolometer are reviewed, including the experimental data and modern noise models. Comparative analysis of noise characteristics of the most developed HTS bolometers for application (antenna-coupled microbolometers and bolometers based on silicon micromachining technology) is reported.

It has been established that in plates made of hot-pressed ferroelectric ceramics PZT-19 ($T_c=300^{\circ }$C), after metal electrodes from Ag are burned into opposite surfaces with different depths of mechanical damage, counter-directional stationary deformation gradients and, accordingly, internal electric displacement fields create a stationary flexoelectric effect. As a result, unpolarized ceramics below the Curie temperature become a pyroelectric, and above it become a pyroelectric bolometer. After polishing the less damaged surface and replacing the Ag (valency $v=3$) electrode with Cr ($v=6$) by thermal evaporation in vacuum from the intact surface, a new thermally stable polarization is created, directed from the damaged surface in the interelectrode volume. Such plates have an asymmetric dielectric hysteresis loop, retain the values of the pyroelectric effect and piezoelectric effect in the ferroelectric phase, as well as the bolometric effect in the paraelectric phase after repeated heating cycles to $400^{\circ }$C and cooling to $T_{\mathrm{\text{norm}}}$.

The keV energy sensitivity of superfluid ³He bolometers is due to the extremely small heat capacity of this fluid. At ultra-low temperatures, however, their thermal response may be dominated by a few atomic layers of adsorbed ³He. We report on direct measurements of this effect, as well as on the techniques that allow to suppress it to achieve the highest detection sensitivity.

CUORICINO is a running ~41 kg TeO2 bolometer experiment looking for the ββ(0ν) of ¹³⁰Te. The latest CUORICINO results together with the present background understanding and reduction in view of the next generation ~750 kg TeO₂ experiment CUORE will be presented.

Having long been the realm of molecular chemistry, astronomy, and plasma diagnostics, the upper millimeter-wave band (∼100 to 300 GHz) and the THz region above it have recently become the subject of heightened activity in the engineering community because of exciting new technology (e.g., sub-picosecond optoelectronics) and promising new “terrestrial” applications (e.g., counter-terrorism and medical imaging). The most challenging of these applications are arguably those that demand remote sensing at a stand-off of roughly 10 m or more between the target and the sensor system. As in any other spectral region, remote sensing in the THz region brings up the complex issues of sensor modality and architecture, free-space electromagnetic effects and components, transmit and receive electronics, signal processing, and atmospheric propagation. Unlike other spectral regions, there is not much literature that addresses these issues from a conceptual or system-engineering viewpoint. So a key theme of this chapter is to review or derive the essential engineering concepts in a comprehensive fashion, starting with fundamental principles of electromagnetics, quantum mechanics, and signal processing, and building up to trade-off formulations using system-level metrics such as noiseequivalent power and receiver operating characteristics. A secondary theme is to elucidate aspects of the THz region and its incumbent technology that are unique, whether advantageous or disadvantageous, relative to other spectral regions. The end goal is to provide a useful tutorial for graduate students or practicing engineers considering the upper mm-wave or THz regions for system research or development.

Multi-color narrow-band Salisbury Screen and Jaumann Absorbers combined with optimized thick Si₃N₄ support layers are designed for wavelength selectivity in 7 ~ 14μm wavelength band. The Jaumann Absorbers are adopted as a vertically ‘stacked’ pixel structure to save space and enhance resolution compared against ‘tiled’ structure (pixels lying in a common plane).

The E and B Experiment (EBEX) is a balloon-borne polarimeter designed to measure the polarization of the cosmic microwave background radiation and to characterize the polarization of galactic dust. EBEX was launched December 29, 2012 and circumnavigated Antarctica observing ∼6,000 square degrees of sky during 11 days at three frequency bands centered around 150, 250 and 410 GHz. EBEX was the first experiment to operate a kilo-pixel array of transition-edge sensor bolometers and a continuously rotating achromatic half-wave plate aboard a balloon platform. It also pioneered the use of detector readout based on digital frequency domain multiplexing.

We describe the temperature calibration of the experiment. The gain response of the experiment is calibrated using a two-step iterative process. We use signals measured on passes across the Galactic plane to convert from readout-system counts to power. The effective smoothing scale of the EBEX optics and the star camera-to-detector offset angles are determined through x² minimization using the compact HII region RCW 38. This two-step process is initially performed with parameters measured before the EBEX 2013 flight and then repeated until the calibration factor and parameters converge.

The Superconducting Quantum Interference Device (SQUID) has been used and proposed often to read out low-temperature detectors for astronomical instruments. A multiplexed SQUID readout for currently envisioned astronomical detector arrays, which will have tens of thousands of pixels, is still challenging with the present technology. We present a new, advanced multiplexing concept and its prototype development that will allow for the readout of 1,000–10,000 detectors with only three pairs of wires and a single microwave coaxial cable.

TeO₂ bolometric detectors have shown to be a promizing technique for Neutrinoless Double Beta Decay (ββ(0ν)) research. With an analyzed statistics of ~18.14 kg ¹³⁰Te × years the CUORICINO experiment has reached a limit on ¹³⁰Te half life for this decay of 2.94×10²⁴ years (90% C.L.). After an intense R&D aimed to background reduction, the next generation CUORE experiment is presently under construcion and foreseen to take data in 2013. Its sensitivity on the electron neutrino Majorana mass 〈m_ee〉 is expected to probe the Inverted Hierarchy Region (IHR) of the neutrino mass spectrum.