Low noise MgB2 hot electron bolometer mixer operated at 5.3 THz and at 20 K
Journal article, 2021
We have demonstrated a low noise superconducting MgB2 hot electron bolometer (HEB) mixer working at the frequency of 5.3 terahertz (THz) with 20 K operation temperature. The bolometer consists of a 7 nm thick MgB2 submicrometer bridge contacted with a spiral antenna to couple THz radiation through a high resistive Si lens, and it has a superconducting critical temperature of 38 K. By using hot/cold blackbody loads and a Mylar beam splitter all in vacuum and applying a 5.25 THz far-infrared gas laser as a local oscillator, we measured a minimal double sideband receiver noise temperature of 3960 K at the LO power of 9.5 mu W. This can be further reduced to 2920 K if a Si lens with an antireflection coating optimized at this frequency and a 3 mu m beam splitter are used. The measured intermediate frequency (IF) noise bandwidth is 9.5 GHz. The low noise, wide IF bandwidth mixers, which can be operated in a compact, low dissipation Stirling cooler, are more suitable for space applications than the existing HEB mixers. Furthermore, we likely observed a signature of the double-gap in MgB2 by comparing current-voltage curves pumped at 5.3 and 1.6 THz.
Author
Y. Gan
University of Groningen
Netherlands Institute for Space Research (SRON)
B. Mirzaei
Delft University of Technology
Netherlands Institute for Space Research (SRON)
J. R. G. D. Silva
Netherlands Institute for Space Research (SRON)
University of Groningen
J. Chang
Delft University of Technology
Serguei Cherednichenko
Chalmers, Microtechnology and Nanoscience (MC2), Terahertz and Millimetre Wave Laboratory
F. van der Tak
University of Groningen
Netherlands Institute for Space Research (SRON)
J. R. Gao
Netherlands Institute for Space Research (SRON)
Delft University of Technology
Applied Physics Letters
0003-6951 (ISSN) 1077-3118 (eISSN)
Vol. 119 20 202601Photon counting superconducting detectors for deep space laser communication
Swedish National Space Board (198/16), 2017-01-01 -- 2019-12-31.
Fiber Integrated MgB2 Single Photon Detectors
Swedish Research Council (VR) (2019-04345), 2020-01-01 -- 2023-12-31.
Subject Categories
Atom and Molecular Physics and Optics
Other Physics Topics
Other Electrical Engineering, Electronic Engineering, Information Engineering
DOI
10.1063/5.0070153