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arXiv · 1009.4676

Optical NEP in Hot-Electron Nanobolometers

Boris S. Karasik·Robin Cantor
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Abstract

For the first time, we have measured the optical noise equivalent power (NEP) in titanium (Ti) superconducting hot-electron nanobolometers (nano-HEBs). The bolometers were 2{\mu}mx1{\mu}mx20nm and 1{\mu}mx1{\mu}mx20nm planar antenna-coupled devices. The measurements were done at {\lambda} = 460 {\mu}m using a cryogenic black body radiation source delivering optical power from a fraction of a femtowatt to a few 100s of femtowatts. A record low NEP = 3x10^{-19} W/Hz^{1/2} at 50 mK has been achieved. This sensitivity meets the requirements for SAFARI instrument on the SPICA telescope. The ways for further improvement of the nano-HEB detector sensitivity are discussed.

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Boris S. Karasik, Robin Cantor. 2010-09-23. Optical NEP in Hot-Electron Nanobolometers. https://arxiv.org/abs/1009.4676

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