Noise and IF Gain Bandwidth of a Balanced Waveguide NbN/GaN Hot Electron Bolometer Mixer Operating at 1.3 THz
Artikel i vetenskaplig tidskrift, 2018

In this paper, we present the comprehensive characterization
of a waveguide balanced phonon-cooled NbN hot electron
bolometer (HEB) mixer on aGaNbuffer-layer operating at approximately
1.3 terahertz (THz). The measured uncorrected double
sideband noise temperature was as low as 750 K at 1 GHz
intermediate frequency (IF) and 900 K at 4 GHz IF, respectively,
and suggests a noise bandwidth of 7 GHz. Moreover, the IF gain
bandwidth of the HEB itself was deduced from a mixing experiment
with a second monochromatic THz signal source and has
shown a 3 dB roll-off at 5.5 GHz. The contribution of the HEB
mixer on the overall receiver noise temperature was determined
to be in the order of 300 K or 5 hf/k considering losses in the
RF transmission path and the waveguide components as well as
accounting for the receiver conversion loss, which was deduced
from the U-factor method. The achieved performance sets a new
benchmark for futureTHz instruments and emphasizes the technological
readiness of waveguide-based NbN HEB mixers employing
a GaN buffer-layer featuring significantly improved IF bandwidth
without compromising on the receiver’s noise temperature.

terahertz (THz) receiver

NbN thin film

Hot electron bolometer (HEB) mixer


Sascha Krause

GARD teknik

Denis Meledin

GARD teknik

Vincent Desmaris

GARD teknik

Alexey Pavolotskiy

GARD teknik

Hawal Marouf Rashid

Chalmers, Rymd-, geo- och miljövetenskap, Avancerad mottagarutveckling

Victor Belitsky

GARD teknik

IEEE Transactions on Terahertz Science and Technology

2156-342X (ISSN)

Vol. 8 3 365-371




Annan elektroteknik och elektronik