Records |
Author |
Beebe, M. R.; Beringer, D. B.; Burton, M. C.; Yang, K.; Lukaszew, R. A. |
Title |
Stoichiometry and thickness dependence of superconducting properties of niobium nitride thin films |
Type |
Journal Article |
Year |
2016 |
Publication |
Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films |
Abbreviated Journal |
Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films |
Volume |
34 |
Issue |
2 |
Pages |
021510 (1 to 4) |
Keywords |
potential plagiarism, possible plagiarism, NbN films |
Abstract |
The current technology used in linear particle accelerators is based on superconducting radio frequency (SRF) cavities fabricated from bulk niobium (Nb), which have smaller surface resistance and therefore dissipate less energy than traditional nonsuperconducting copper cavities. Using bulk Nb for the cavities has several advantages, which are discussed elsewhere; however, such SRF cavities have a material-dependent accelerating gradient limit. In order to overcome this fundamental limit, a multilayered coating has been proposed using layers of insulating and superconducting material applied to the interior surface of the cavity. The key to this multilayered model is to use superconducting thin films to exploit the potential field enhancement when these films are thinner than their London penetration depth. Such field enhancement has been demonstrated in MgB2 thin films; here, the authors consider films of another type-II superconductor, niobium nitride (NbN). The authors present their work correlating stoichiometry and superconducting properties in NbN thin films and discuss the thickness dependence of their superconducting properties, which is important for their potential use in the proposed multilayer structure. While there are some previous studies on the relationship between stoichiometry and critical temperature TC, the authors are the first to report on the correlation between stoichiometry and the lower critical field HC1. |
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 |
0734-2101 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference ![sorted by Conference field, descending order (down)](img/sort_desc.gif) |
|
Notes |
Potential plagiarism for 1503 |
Approved |
no |
Call Number |
|
Serial |
1504 |
Permanent link to this record |
|
|
|
Author |
Semenov, A.; Richter, H.; Hübers, H.-W.; Smirnov, K.; Voronov, B.; Gol'tsman, G. |
Title |
Development of terahertz superconducting hot-electron bolometer mixers |
Type |
Conference Article |
Year |
2003 |
Publication |
Proc. 6th European Conf. Appl. Supercond. |
Abbreviated Journal |
Proc. 6th European Conf. Appl. Supercond. |
Volume |
181 |
Issue |
|
Pages |
2960-2965 |
Keywords |
NbN HEB mixers |
Abstract |
We present recent results of the development of phonon cooled hot-electron bolometric (HEB) mixers for airborne and balloon borne terahertz heterodyne receivers. Three iomportant issues have been addresses: the quality of NbN films the HEB mixers were made from, the spectral properties of the HEB mixers and the local oscillator power required for optical operation. Studies with an atomic force microscope indicate, that the performance of the HEB mixer might have been effected by the microstructure of the NbN film. Antenna gain and noise temperature were investigated at terahertz frequencies for a HEB embedded in either log-spiral or twin-slot feed antenna. Comparison suggests that at frequencies above 3 THz the spiral feed provides better overall performance. At 1.6 THz, a power of 2.5 µW was required from the local oscillator for optimal operation of the HEB mixer. |
Address |
Sorrento, Italy |
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 |
0750309814, 978-0750309813 |
Medium |
|
Area |
|
Expedition |
|
Conference ![sorted by Conference field, descending order (down)](img/sort_desc.gif) |
|
Notes |
|
Approved |
no |
Call Number |
|
Serial |
1505 |
Permanent link to this record |
|
|
|
Author |
Richter, H.; Semenov, A.; Hubers, H.-W.; Smirnov, K.; Gol’tsman, G.; Voronov, B. |
Title |
Phonon cooled hot-electron bolometric mixer for 1-5 THz |
Type |
Conference Article |
Year |
2004 |
Publication |
Proc. 29th IRMMW / 12th THz |
Abbreviated Journal |
Proc. 29th IRMMW / 12th THz |
Volume |
|
Issue |
|
Pages |
241-242 |
Keywords |
NbN HEB mixers |
Abstract |
Heterodyne receivers for applications in astronomy and planetary research need quantum limited sensitivity. In instruments which are currently built for SOFIA and Herschel, superconducting hot electron bolometers (HEB) are used to achieve this goal at frequencies above 1.4 THz. In order to optimize the performance for this frequency of hot electron bolometer mixers with different in-plane dimensions and logarithmic-spiral feed antennas have been investigated. Their noise temperatures and beam patterns were measured. Above 3 THz the best performance was achieved with a superconducting bridge of 2.0/spl times/0.2 /spl mu/m/sup 2/ incorporated in a logarithmic spiral antenna. The DSB noise temperatures were 2700 K, 4700 and 6400 K at 3.1 THz, 4.3 THz and 5.2 THz, respectively. The results demonstrate that the NbN HEB is very well suited as a mixer for THz heterodyne receivers up to at least 5 THz. |
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 ![sorted by Conference field, descending order (down)](img/sort_desc.gif) |
|
Notes |
|
Approved |
no |
Call Number |
|
Serial |
1506 |
Permanent link to this record |
|
|
|
Author |
Rubtsova, I.; Korneev, A.; Matvienko, V.; Chulkova, G.; Milostnaya, I.; Goltsman, G.; Pearlman, A.; Slysz, W.; Verevkin, A.; Sobolewski, R. |
Title |
Spectral sensitivity, quantum efficiency, and noise equivalent power of NbN superconducting single-photon detectors in the IR range |
Type |
Conference Article |
Year |
2004 |
Publication |
Proc. 29th IRMMW / 12th THz |
Abbreviated Journal |
Proc. 29th IRMMW / 12th THz |
Volume |
|
Issue |
|
Pages |
461-462 |
Keywords |
NbN SSPD, SNSPD |
Abstract |
We have developed nanostructured NbN superconducting single-photon detectors capable of GHz-rate photon counting in the 0.4 to 5 /spl mu/m wavelength range. Quantum efficiency of 30%, dark count rate 3/spl times/10/sup -4/ s/sup -1/, and NEP=10/sup -20/ W/Hz/sup -1/2/ have been measured at the 1.3-/spl mu/m wavelength for the device operating at 2.0 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 ![sorted by Conference field, descending order (down)](img/sort_desc.gif) |
|
Notes |
|
Approved |
no |
Call Number |
|
Serial |
1507 |
Permanent link to this record |
|
|
|
Author |
Meledin, D.; Tong, C.-Y. E.; Blundell, R.; Goltsman, G. |
Title |
Measurement of intermediate frequency bandwidth of hot electron bolometer mixers at terahertz frequency range |
Type |
Journal Article |
Year |
2003 |
Publication |
IEEE Microw. Wireless Compon. Lett. |
Abbreviated Journal |
IEEE Microw. Wireless Compon. Lett. |
Volume |
13 |
Issue |
11 |
Pages |
493-495 |
Keywords |
waveguide NbN HEB mixers |
Abstract |
We have developed a new experimental setup for measuring the IF bandwidth of superconducting hot electron bolometer mixers. In our measurement system we use a chopped hot filament as a broadband signal source, and can perform a high-speed IF scan with no loss of accuracy when compared to coherent methods. Using this technique we have measured the 3 dB IF bandwidth of hot electron bolometer mixers, designed for THz frequency operation, and made from 3-4 nm thick NbN film deposited on an MgO buffer layer over crystalline quartz. |
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 |
1531-1309 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference ![sorted by Conference field, descending order (down)](img/sort_desc.gif) |
|
Notes |
|
Approved |
no |
Call Number |
|
Serial |
1509 |
Permanent link to this record |