Showing papers by "A. D. Turner published in 2008"
TL;DR: In this article, the authors report progress toward large arrays of sensitive TES bolometers for submillimeter and far-infrared wavelengths with noise equivalent power (NEP) suitable for either imaging from a cooled space telescope or ground-based spectroscopy.
Abstract: We report progress toward large arrays of sensitive TES bolometers for submillimeter and far-infrared wavelengths with noise equivalent power (NEP) suitable for either imaging from a cooled space telescope or ground based spectroscopy. The arrays are based on a pixel design that makes use of a distributed transition edge sensor (TES) coupled to a slot antenna array. We have electrically characterized prototype detectors consisting of 256 TiN hot-electron TES microbolometers biased in parallel with T
c
=50 mK. The measured electron-phonon thermal conductance of prototype devices is as low as 1.1 pW/K at 50 mK corresponding to an electrical NEP of 4×10−19 W/Hz1/2. The time constant of two detectors with different geometries and transition widths was measured under a range of bias conditions. We have measured time constants ≳10−3 seconds, which is long enough for straightforward multiplexing with existing multiplexer technology.
19 citations
TL;DR: In this article, the thermal and DC electrical properties of transition-edge sensing (TES) bolometers to be employed on the SPIDER experiment, a balloon-based observatory for studying the polarization of the cosmic microwave background (CMB), were measured.
Abstract: We have fabricated and measured the thermal and DC electrical properties of transition-edge sensing (TES) bolometers to be employed on the SPIDER experiment, a balloon-based observatory for studying the polarization of the cosmic microwave background (CMB). The bolometers consist of Al and Ti thermistors in series and a termination resistor which couples to an on-chip, polarization sensitive, 150 GHz slot-array antenna through a superconducting microstrip transmission line. Several important parameters were measured. Transition temperature measurements were performed by measuring the Johnson noise in the Ti thermistor. Current-voltage characteristic measurements were performed at various temperatures allowing for the deduction of the thermal conductance and the temperature coefficient of resistance. Electrical noise equivalent power was measured to sub-Hertz frequencies. Finally, the time constant of the bolometers was measured within the Al and Ti transitions where electrothermal feedback speeds up the bolometer response compared with the natural time constant measured just above the Ti transition temperature. The results of these measurements are within the design specifications for SPIDER.
12 citations