An array scalable zero-bias far-IR detector with noise thermometry readout

23 Jul 2019, 17:45
1h 15m
Piazza Città di Lombardia (Milano)

Piazza Città di Lombardia

Milano

Piazza Città di Lombardia, 1, 20124 Milano MI
Poster Low Temperature Detector Development and Physics Poster session

Speaker

Dr Boris Karasik (Jet Propulsion Laboratory)

Description

We report on a new development effort to achieve an array of ultra-sensitive (NEP < 1E-20 W/sqrt(Hz)) far-IR detectors for applications in spectrometers on Origins Space Telescope (OST) or similar low-background platforms. The detector uses a submicron-size hot-electron bolometer (HEB) sensor made from normal metal (non-superconducting Ti) coupled to a planar microantenna. The detector does not require any bias (dc or rf). The Johnson Noise Thermometry using a quantum noise limited microwave amplifier (LNA) allows for the direct read of an increase of the electron temperate caused by the absorbed far-IR radiation. At 50 mK, the NEP is less than 1E-20 W/sqrt(Hz) is expected whereas the dynamic range is 60-100 dB. Multiplexing of a 1000-pixel array is feasible using a single LNA with a bank of narrowband bandpass filters for channel multiplexing.
In this paper, we will present an initial experimental study of the electrical NEP in a 1µm × 1µm detector. A set of superconducting narrow band-pass (Q = 100-1000) and low-pass filters defines the readout bandwidth around the center frequency of 1.5 GHz. A commercial HEMT LNA with the noise temperature T_A ≈ 1 K largely determines the system sensitivity (NEP ≈ 1E-19 W/sqrt(Hz) @ 50 mK). Electrical NEP is measured by sending a dc current through the device and measuring a change of the output noise power caused by the heating. Switching to a quantum noise limited parametric kinetic inductance amplifier will allows us to reach an NEP close to 1E-20 W/sqrt(Hz). The next phase of this work will be using much smaller HEB devices (e.g., 0.5µm × 0.25µm) where NEP = 3E-21 W/sqrt(Hz) is predicted. Because of the very high dynamic range and optical saturating power, various additional higher background or/and higher operating temperature applications of such a sensor are envisioned.

Less than 5 years of experience since completion of Ph.D N
Student (Ph.D., M.Sc. or B.Sc.) N

Primary author

Dr Boris Karasik (Jet Propulsion Laboratory)

Co-authors

Dr Peter Day (Jet Propulsion Laboratory) Dr Anders Skalare (Jet Propulsion Laboratory)

Presentation Materials