| |
Records |
Links |
|
Author |
Beck, M.; Klammer, M.; Lang, S.; Leiderer, P.; Kabanov, V. V.; Gol’tsman, G. N.; Demsar, J. |
|
| |
Title |
Energy-gap dynamics of superconducting NbN thin films studied by time-resolved terahertz spectroscopy |
Type |
Miscellaneous |
| |
Year |
2011 |
Publication |
arXiv |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages  |
|
|
| |
Keywords |
NbN thin film, energy gap dynamics |
|
| |
Abstract |
Using time-domain Terahertz spectroscopy we performed direct studies of the photoinduced suppression and recovery of the superconducting gap in a conventional BCS superconductor NbN. Both processes are found to be strongly temperature and excitation density dependent. The analysis of the data with the established phenomenological Rothwarf-Taylor model enabled us to determine the bare quasiparticle recombination rate, the Cooper pair-breaking rate and the electron-phonon coupling constant, \lambda = 1.1 +/- 0.1, which is in excellent agreement with theoretical estimates. |
|
| |
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 |
Duplicated as 641 |
Approved |
no |
|
| |
Call Number |
|
Serial |
1388 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Henrich, D.; Dorner,S.; Hofherr, M.; Il'in, K.; Semenov, A.; Heintze, E.; Scheffler, M.; Dressel, M.; Siegel, M. |
|
| |
Title |
Broadening of hot-spot response spectrum of superconducting NbN nanowire single-photon detector with reduced nitrogen content |
Type |
Journal Article |
| |
Year |
2012 |
Publication |
|
Abbreviated Journal |
J. Appl. Phys. |
|
| |
Volume |
112 |
Issue |
|
Pages |
|
|
| |
Keywords |
SSPD, SNSPD, magnetron sputtering, spectrum, NbN film, nitrogen concentration |
|
| |
Abstract |
The spectral detection efficiency and the dark count rate of superconducting nanowire
single-photon detectors (SNSPD) have been studied systematically on detectors made from thin
NbN films with different chemical compositions. Reduction of the nitrogen content in the 4 nm
thick NbN films results in a decrease of the dark count rates more than two orders of magnitude
and in a red shift of the cut-off wavelength of the hot-spot SNSPD response. The observed
phenomena are explained by an improvement of uniformity of NbN films that has been confirmed
by a decrease of resistivity and an increase of the ratio of the measured critical current to the
depairing current. The latter factor is considered as the most crucial for both the cut-off
wavelength and the dark count rates of SNSPD. Based on our results we propose a set of criteria
for material properties to optimize SNSPD in the infrared spectral region. VC 2012 American
Institute of Physics. [http://dx.doi.org/10.1063/1.4757625] |
|
| |
Address |
|
|
| |
Corporate Author |
D. Henrich, S. Dorner, M. Hofherr, K. Il'in, A. Semenov, E. Heintze, M. Scheffler, M. Dressel, M. Siegel |
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
Broadening of hot-spot response spectrum of superconducting NbN nanowire single-photon detector with reduced nitrogen content |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
RPLAB @ seleznev @ |
Serial |
877 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Khosropanah, Pourya |
|
| |
Title |
NbN and NbTiN hot electron bolometer THz mixers |
Type |
Book Whole |
| |
Year |
2003 |
Publication |
Chalmers University of Technology |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
|
|
| |
Keywords |
HEB mixer, hot electron bolometer mixer, NbN, NbTiN, superconducting detector, heterodyne receiver, THz mixer, submillimeter mixer, quasioptical receiver, double slot antenna, twin slot antenna, spiral antenna, receiver noise, FTS, Fourier Transform Spectrometer |
|
| |
Abstract |
The thesis reports the development of Hot Electron Bolometer (HEB) mixers for radio astronomy heterodyne receivers in THz frequency range. Part of this work is the fabrication of HEB devices, which are based on NbN or NbTiN superconducting thin films (â‰<a4>5 nm). They are integrated with wideband spiral or double-slot planar antennas. The mixer chips are incorporated into a quasi-optical receiver. The experimental part of this work focuses on the characterization of the receiver as a whole, and the HEB mixers as a part. Double side band receiver noise temperature and the IF bandwidth are reported for frequencies from 0.7 THz up to 2.6 THz. The spectrum of the direct response of HEB integrated with dierent antennas are measured using Fourier Transform Spectrometer (FTS). The effect of the bolometer size on total receiver performance and the LO power requirements is also discussed. A high-yield and reliable process for fabrication of NbN HEB mixers have been achieved. Over 100 devices with different bolometer geometry, film property and also different antennas have been fabricated and measured. The measured data enables us to discuss the impact of different parameters to the receiver overall performance.
This work has provided NbN HEB mixers to the following receivers:
TREND (Terahertz REceiver with NbN HEB Device) operating at 1.25-1.5 THz, installed in AST/RO Submillimeter Wave Telescope, Amundsen/Scott South Pole Station, in 2002-2003.
Band 6-low (1.410-1.700 THz) and 6-high (1.700-1.920 THz) of the HIFI (Heterodyne Instrument for Far Infra-red) in the Herschel Space Observatory, due to launch in 2007 by ESA (European Space Agency).
Besides, there has been continuous efforts to develop better models to explain the mixer performance more accurately. They are based on two temperature model for electrons and phonons and solving one-dimensional heat balance equations along the bolometer. The principles of these models are illustrated and the calculated results are compared with measured data. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
Ph.D. thesis |
|
| |
Publisher |
Chalmers University of Technology |
Place of Publication |
Göteborg |
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 |
910 |
|
| 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 |
Arutyunov, K. Y.; Ramos-Álvarez, A.; Semenov, A. V.; Korneeva, Y. P.; An, P. P.; Korneev, A. A.; Murphy, A.; Bezryadin, A.; Gol’tsman, G. N. |
|
| |
Title |
Quasi-1-dimensional superconductivity in highly disordered NbN nanowires |
Type |
Miscellaneous |
| |
Year |
2016 |
Publication |
arXiv |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
|
|
| |
Keywords |
narrow NbN nanowires, BCS |
|
| |
Abstract |
The topic of superconductivity in strongly disordered materials has attracted a significant attention. In particular vivid debates are related to the subject of intrinsic spatial inhomogeneity responsible for non-BCS relation between the superconducting gap and the pairing potential. Here we report experimental study of electron transport properties of narrow NbN nanowires with effective cross sections of the order of the debated inhomogeneity scales. We find that conventional models based on phase slip concept provide reasonable fits for the shape of the R(T) transition curve. Temperature dependence of the critical current follows the text-book Ginzburg-Landau prediction for quasi-one-dimensional superconducting channel Ic~(1-T/Tc)^3/2. Hence, one may conclude that the intrinsic electronic inhomogeneity either does not exist in our structures, or, if exist, does not affect their resistive state properties. |
|
| |
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 |
Duplicated as 1332 |
Approved |
no |
|
| |
Call Number |
|
Serial |
1338 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Murphy, A.; Semenov, A.; Korneev, A.; Korneeva, Y.; Gol’tsman, G.; Bezryadin, A. |
|
| |
Title |
Dark counts initiated by macroscopic quantum tunneling in NbN superconducting photon detectors |
Type |
Miscellaneous |
| |
Year |
2014 |
Publication |
arXiv |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
|
|
| |
Keywords |
NbN SSPD |
|
| |
Abstract |
We perform measurements of the switching current distributions of three w = 120 nm wide, 4 nm thick NbN superconducting strips which are used for single-photon detectors. These strips are much wider than the diameter the vortex cores, so they are classified as quasi-two-dimensional (quasi-2D). We discover evidence of macroscopic quantum tunneling by observing the saturation of the standard deviation of the switching distributions at temperatures around 2 K. We analyze our results using the Kurkijarvi-Garg model and find that the escape temperature also saturates at low temperatures, confirming that at sufficiently low temperatures, macroscopic quantum tunneling is possible in quasi-2D strips and can contribute to dark counts observed in single photon detectors. |
|
| |
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 |
murphy2014dark |
Serial |
1356 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Смирнов, Константин Владимирович |
|
| |
Title |
Создание приборов на сверхпроводниковых счетчиках фотонов и методов диагностики КМОП микросхем, гетероструктур и лазеров на квантовых точках |
Type |
Report |
| |
Year |
2009 |
Publication |
|
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
|
|
| |
Keywords |
NbN SSPD |
|
| |
Abstract |
Этап №1 (дата окончания: 30.09.2009)
Разработана методика изготовления сверхпроводниковых однофотонных детекторов (SSPD) с монокристаллической структурой пленки сверхмалой толщины. Изготовлены экспериментальные образцы сверхпроводниковых однофотонных детекторов (SSPD). Разработана методика пакетирования сверхпроводникового однофотонного детектора в оптический узел с одномодовым оптоволокном. Изготовлены экспериментальные образцы приемных модулей на основе однофотонных сверхпроводниковых детекторов из NbN-нанопленок.
Этап №2 (дата окончания: 28.10.2009)
Разработаны методы диагностики КМОП микросхем, гетероструктур и лазеров на квантовых точках и методика измерения мощности излучения полупроводниковых лазеров на квантовых точках с использованием сверхпроводниковых однофотонных детекторов (SSPD). Проведена технико-экономическая оценка рыночного потенциала полученных результатов. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Министерство образования и науки РФ |
Place of Publication |
|
Editor |
|
|
| |
Language |
Russian |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
Отчет о НИР/НИОКР; Министерство образования и науки РФ; Номер гранта (контракта): 02.513.11.3446; Дата гранта (контракта): 03.06.2009 |
Approved |
no |
|
| |
Call Number |
|
Serial |
1828 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Il'in, K.; Siegel, M.; Semenov, A.; Engel, A.; Hübers, H.-W.; Hollmann, E.; Gol'tsman, G.; Voronov, B. |
|
| |
Title |
Thickness dependence of superconducting properties of ultrathin Nb and NbN films |
Type |
Conference Article |
| |
Year |
2004 |
Publication |
AKF-Frühjahrstagung |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
|
|
| |
Keywords |
Nb, NbN films, has potential plagiarism |
|
| |
Abstract |
|
|
| |
Address |
Berlin-Adlershof |
|
| |
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 |
1503 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Hübers, Heinz-Wilhelm; Semenov, A.; Richter, H.; Smirnov, K.; Gol'tsman, G.; Voronov, B. |
|
| |
Title |
Phonon cooled far-infrared hot electron bolometer mixer |
Type |
Abstract |
| |
Year |
2002 |
Publication |
NASA/ADS |
Abbreviated Journal |
NASA/ADS |
|
| |
Volume |
|
Issue |
|
Pages |
|
|
| |
Keywords |
NbN HEB mixers |
|
| |
Abstract |
Heterodyne receivers for applications in astronomy need quantum-limited sensitivity. At frequencies above 1.4 THz superconducting hot electron bolometers (HEB) can be used to achieve this goal. We present results of the development of a quasi-optical phonon-cooled NbN HEB mixer for GREAT, the German heterodyne receiver for SOFIA. Different mixers with logarithmic spiral and double slot feed antennas have been investigated with respect to their noise temperature, conversion loss, linearity and beam pattern at several frequencies between 0.7 THz and 5.2 THz. At 2.5 THz a double sideband noise temperature of 2200 K was achieved. The conversion loss was 16 dB. The response of the mixer was linear up to 400 K load temperature. This performance was verified by measuring an emission line of methanol at 2.5 THz. The results demonstrate that the NbN HEB is very well suited as a mixer for FIR heterodyne receivers. |
|
| |
Address |
Monterey, CA |
|
| |
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 |
Far-IR, Sub-mm & MM Detector Technology Workshop, 1-3 April 2002 |
|
| |
Notes |
id.37 |
Approved |
no |
|
| |
Call Number |
|
Serial |
1534 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Okunev, O.; Smirnov, K.; Chulkova, G.; Korneev, A.; Lipatov, A.; Gol'tsman, G.; Zhang, J.; Slysz, W.; Verevkin, A.; Sobolewski, Roman |
|
| |
Title |
Ultrafast NBN hot-electron single-photon detectors for electronic applications |
Type |
Abstract |
| |
Year |
2002 |
Publication |
Abstracts 8-th IUMRS-ICEM |
Abbreviated Journal |
Abstracts 8-th IUMRS-ICEM |
|
| |
Volume |
|
Issue |
|
Pages |
|
|
| |
Keywords |
NbN SSPD, SNSPD |
|
| |
Abstract |
We present a new, simple to manufacture, single-photon detector (SPD), which can work from ultraviolet to near-infrared wavelengths of optical radiation and combines high speed of operation, high quantum efficiency (QE), and very low dark counts. The devices are superconducting and operate at temperature below 5 K. The physics of operation of our SPD is based on formation of a photon-induced resistive hotspot and subsequent appearance of a transient resistive barrier across an ultrathin and submicron-wide superconductor. |
|
| |
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 |
8th IUMRS International Conference on Electronic Materials |
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
|
Serial |
1532 |
|
| Permanent link to this record |
