TY - JOUR
T1 - Performance of a bridge-type TES microcalorimeter, excess noise characteristics and dependence of sensitivity on current
AU - Takei, Y.
AU - Tanaka, K.
AU - Fujimoto, R.
AU - Ishisaki, Y.
AU - Morita, U.
AU - Morooka, T.
AU - Oshima, T.
AU - Futamoto, K.
AU - Hiroike, T.
AU - Koga, T.
AU - Mitsuda, K.
AU - Ohashi, T.
AU - Yamasaki, N. Y.
AU - Iyomoto, N.
AU - Ichitsubo, T.
AU - Sato, K.
AU - Fujimori, T.
AU - Shinozaki, K.
AU - Nakayama, S.
AU - Chinone, K.
N1 - Funding Information:
Authors are very grateful to Dr. Koji Kamiya, who kindly calculated the effectiveness of the magnetic shield used in our experiment. We thank Dr. David Willis for his careful reading and correction of our manuscript. This work was supported by the Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan (No. 12304009, 13440079, 14204017).
PY - 2004/5/1
Y1 - 2004/5/1
N2 - Fully utilizing the benefit of strong electrothermal feedback, we achieved the energy resolution of 6.6 eV (FWHM) at 5.9 keV and a fast response time of 74 μs with our bridge-type Ti/Au transition-edge sensor (TES) microcalorimeter. The energy resolution of this device was limited by a noise that was larger than the intrinsic noise and the readout noise. This noise only appeared when the current through the TES was large (≳10 μA), and its level, defined as a fluctuation amplitude of the current through the TES, was in proportion to the inverse of the TES resistance. We also found that the TES sensitivity depended on the current through the TES, normalized with the critical current of the TES. When the current exceeded about 1% of the critical current, the TES sensitivity was significantly degraded. The critical current clearly correlated with the TES sensitivity, and hence the signal-to-noise ratio at the optimal operating point, among devices with different TES size and thickness. Thus, the critical current is one of the key parameters to determine the performance of the TES microcalorimeter.
AB - Fully utilizing the benefit of strong electrothermal feedback, we achieved the energy resolution of 6.6 eV (FWHM) at 5.9 keV and a fast response time of 74 μs with our bridge-type Ti/Au transition-edge sensor (TES) microcalorimeter. The energy resolution of this device was limited by a noise that was larger than the intrinsic noise and the readout noise. This noise only appeared when the current through the TES was large (≳10 μA), and its level, defined as a fluctuation amplitude of the current through the TES, was in proportion to the inverse of the TES resistance. We also found that the TES sensitivity depended on the current through the TES, normalized with the critical current of the TES. When the current exceeded about 1% of the critical current, the TES sensitivity was significantly degraded. The critical current clearly correlated with the TES sensitivity, and hence the signal-to-noise ratio at the optimal operating point, among devices with different TES size and thickness. Thus, the critical current is one of the key parameters to determine the performance of the TES microcalorimeter.
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U2 - 10.1016/j.nima.2003.12.025
DO - 10.1016/j.nima.2003.12.025
M3 - Article
AN - SCOPUS:11144354896
SN - 0168-9002
VL - 523
SP - 134
EP - 146
JO - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
JF - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
IS - 1-2
ER -