| Records |
| Author |
Trifonov, Andrey; Tong, C. Edward; Lobanov, Yury; Kaurova, Natalia; Blundell, Raymond; Gol’tsman, Gregory |
| Title |
An investigation of the DC and IF performance of silicon-membrane HEB mixer elements |
Type |
Conference Article |
| Year |
2015 |
Publication |
Proc. 26th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 26th Int. Symp. Space Terahertz Technol. |
Volume  |
|
Issue |
|
Pages |
40 |
| Keywords |
silicon-membrane HEB waveguide mixer |
| Abstract |
We report on our initial development towards a 2x2 multi-pixel HEB waveguide mixer for operation at 1.4 THz. We have successfully fabricated devices comprising an NbN bridge integrated with antenna test structure using a silicon membrane as the supporting substrate. DC measurements of the test chips demonstrate critical current from 0.1 – 1mA depending on the size of device, with T c of around 10 K and ΔTc ~ 0.8 K. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
|
Serial |
1160 |
| Permanent link to this record |
| |
|
| |
| Author |
Samsonova, Alena; Zolotov, Philipp; Baeva, Elmira; Lomakin, Andrey; Titova, Nadezhda; Kardakova, Anna; Goltsman, Gregory |
| Title |
Signatures of surface magnetic disorder in thin niobium films |
Type |
Journal Article |
| Year |
2021 |
Publication |
IEEE Trans. Appl. Supercond. |
Abbreviated Journal |
|
| Volume |
|
Issue |
|
Pages |
1-1 |
| Keywords |
Temperature measurement, Temperature dependence, Superconducting magnets, Superconducting transition temperature, Substrates, Resistance, Scattering |
| Abstract |
We present our studies on the evolution of the normal and superconducting properties with thickness of thin Nb films with a low level of non-magnetic disorder (kFl 150 for the thickest film in the set). The analysis of the superconducting behavior points to the presence of magnetic moments, hidden in the native oxide on the surface of Nb films. Using the Abrikosov-Gorkov theory, we obtain the density of surface magnetic moments of 1013 cm-2, which is in agreement with the previously reported data for Nb films. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1051-8223 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
|
Serial |
1162 |
| Permanent link to this record |
| |
|
| |
| Author |
Baeva, E. M.; Titova, N. A.; Veyrat, L.; Sacépé, B.; Semenov, A. V.; Goltsman, G. N.; Kardakova, A. I.; Khrapai, V. S. |
| Title |
Thermal relaxation in metal films bottlenecked by diffuson lattice excitations of amorphous substrates |
Type |
Miscellaneous |
| Year |
2021 |
Publication |
arXiv |
Abbreviated Journal |
arXiv |
| Volume |
|
Issue |
|
Pages |
|
| Keywords |
metal films, NbN, InOx, Au/Ni, thermal relaxation |
| Abstract |
Here we examine the role of the amorphous insulating substrate in the thermal relaxation in thin NbN, InOx, and Au/Ni films at temperatures above 5 K. The studied samples are made up of metal bridges on an amorphous insulating layer lying on or suspended above a crystalline substrate. Noise thermometry was used to measure the electron temperature Te of the films as a function of Joule power per unit of area P2D. In all samples, we observe the dependence P2D∝Tne with the exponent n≃2, which is inconsistent with both electron-phonon coupling and Kapitza thermal resistance. In suspended samples, the functional dependence of P2D(Te) on the length of the amorphous insulating layer is consistent with the linear T-dependence of the thermal conductivity, which is related to lattice excitations (diffusons) for the phonon mean free path smaller than the dominant phonon wavelength. Our findings are important for understanding the operation of devices embedded in amorphous dielectrics. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
|
Serial |
1163 |
| Permanent link to this record |
| |
|
| |
| Author |
Seliverstov, Sergey V.; Rusova, Anastasia A.; Kaurova, Natalya S.; Voronov, Boris M.; Goltsman, Gregory N. |
| Title |
AC-biased superconducting NbN hot-electron bolometer for frequency-domain multiplexing |
Type |
Conference Article |
| Year |
2017 |
Publication |
Proc. 28th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 28th Int. Symp. Space Terahertz Technol. |
| Volume |
|
Issue |
|
Pages |
120-122 |
| Keywords |
NbN HEB mixer |
| Abstract |
We present the results of characterization of fast and sensitive superconducting antenna-coupled THz direct detector based on NbN hot-electron bolometer (HEB) with AC-bias. We discuss the possibility of implementation of the AC-bias for design the readout system from the multi-element arrays of HEBs using standard technique of frequency-domain multiplexing. We demonstrate experimentally that this approach does not lead to significant deterioration of the HEB sensitivity compared with the value obtained for the same detector with DC- bias. Results of a numerical calculations of the HEB responsivity at AC-bias are in a good agreement with the experiment. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
|
Serial |
1174 |
| Permanent link to this record |
| |
|
| |
| Author |
Antipov, S.; Trifonov, A.; Krause, S.; Meledin, D.; Desmaris, V.; Belitsky, V.; Gol’tsman, G. |
| Title |
Gain bandwidth of NbN HEB mixers on GaN buffer layer operating at 2 THz local oscillator frequency |
Type |
Conference Article |
| Year |
2017 |
Publication |
Proc. 28th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 28th Int. Symp. Space Terahertz Technol. |
| Volume |
|
Issue |
|
Pages |
147-148 |
| Keywords |
NbN HEB mixers, GaN buffer-layer, IF bandwidth |
| Abstract |
In this paper, we present IF bandwidth measurement results of NbN HEB mixers, which are employing NbN thin films grown on a GaN buffer-layer. The HEB mixers were operated in the heterodyne regime at a bath temperature of approximately 4.5 K and with a local oscillator operating at a frequency of 2 THz. A quantum cascade laser served as the local oscillator and a reference synthesizer based on a BWO generator (130-160 GHz) and a semiconductor superlattice (SSL) frequency multiplier was used as a signal source. By changing the LO frequency it was possible to record the IF response or gain bandwidth of the HEB with a spectrum analyzer at the operation point, which yielded lowest noise temperature. The gain bandwidth that was recorded in the heterodyne regime at 2 THz amounts to approximately 5 GHz and coincides well with a measurement that has been performed at elevated bath temperatures and lower LO frequency of 140 GHz. These findings strongly support that by using a GaN buffer-layer the phonon escape time of NbN HEBs can be significantly lower as compared to e.g. Si substrate, thus, providing higher gain bandwidth. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
|
Serial |
1175 |
| Permanent link to this record |
