| Records |
| Author |
Dube, I.; Jiménez, D.; Fedorov, G.; Boyd, A.; Gayduchenko, I.; Paranjape, M.; Barbara, P. |
Title  |
Understanding the electrical response and sensing mechanism of carbon-nanotube-based gas sensors |
Type |
Journal Article |
| Year |
2015 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| Volume |
87 |
Issue |
|
Pages |
330-337 |
| Keywords |
carbon nanotubes, CNT detectors, field effect transistors, FET |
| Abstract |
Gas sensors based on carbon nanotube field effect transistors (CNFETs) have outstanding sensitivity compared to existing technologies. However, the lack of understanding of the sensing mechanism has greatly hindered progress on calibration standards and customization of these nano-sensors. Calibration requires identifying fundamental transistor parameters and establishing how they vary in the presence of a gas. This work focuses on modeling the electrical response of CNTFETs in the presence of oxidizing (NO2) and reducing (NH3) gases and determining how the transistor characteristics are affected by gas-induced changes of contact properties, such as the Schottky barrier height and width, and by the doping level of the nanotube. From the theoretical fits of the experimental transfer characteristics at different concentrations of NO2 and NH3, we find that the CNTFET response can be modeled by introducing changes in the Schottky barrier height. These changes are directly related to the changes in the metal work function of the electrodes that we determine experimentally, independently, with a Kelvin probe. Our analysis yields a direct correlation between the ON – current and the changes in the electrode metal work function. Doping due to molecules adsorbed at the carbon-nanotube/metal interface also affects the transfer characteristics. |
| 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 |
0008-6223 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
|
Serial |
1778 |
| Permanent link to this record |
| |
|
| |
| Author |
Sidorova, Maria V.; Divochiy, Alexander; Vakhtomin, Yury B.; Smirnov, Konstantin V. |
| Title |
Ultrafast superconducting single-photon detector with reduced-size active area coupled to a tapered lensed single-mode fiber |
Type |
Conference Article |
| Year |
2015 |
Publication |
Proc. SPIE |
Abbreviated Journal |
|
| Volume |
9504 |
Issue |
|
Pages |
950408 (1 to 9) |
| Keywords |
|
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
International Society for Optics and Photonics |
| 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 |
RPLAB @ sasha @ sidorova2015ultrafast |
Serial |
1051 |
| Permanent link to this record |
| |
|
| |
| Author |
Sidorova, Maria V.; Divochiy, Alexander V.; Vakhtomin, Yury B.; Smirnov, Konstantin V. |
| Title |
Ultrafast superconducting single-photon detector with a reduced active area coupled to a tapered lensed single-mode fiber |
Type |
Journal Article |
| Year |
2015 |
Publication |
J. Nanophoton. |
Abbreviated Journal |
|
| Volume |
9 |
Issue |
1 |
Pages |
093051 |
| Keywords |
SSPD, SNSPD |
| Abstract |
This paper presents an ultrafast niobium nitride (NbN) superconducting single-photon detector (SSPD) with an active area of 3×3 μm2 that offers better timing performance metrics than the previous SSPD with an active area of 7×7 μm2. The improved SSPD demonstrates a record timing jitter (<25 ps), an ultrashort recovery time (<2 ns), an extremely low dark count rate, and a high detection efficiency in a wide spectral range from visible part to near infrared. The record parameters were obtained due to the development of a new technique providing effective optical coupling between a detector with a reduced active area and a standard single-mode telecommunication fiber. The advantages of the new approach are experimentally confirmed by taking electro-optical measurements. |
| 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 |
1934-2608 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
10.1117/1.JNP.9.093051 |
Approved |
no |
| Call Number |
RPLAB @ sasha @ |
Serial |
1052 |
| Permanent link to this record |
| |
|
| |
| Author |
Galin, M. A.; Klushin, A. M.; Kurin, V. V.; Seliverstov, S. V.; Finkel, M. I.; Goltsman, G. N.; Müller, F.; Scheller, T.; Semenov, A. D. |
| Title |
Towards local oscillators based on arrays of niobium Josephson junctions |
Type |
Journal Article |
| Year |
2015 |
Publication |
Supercond. Sci. Technol. |
Abbreviated Journal |
Supercond. Sci. Technol. |
| Volume |
28 |
Issue |
5 |
Pages |
055002 (1 to 7) |
| Keywords |
Josephson junction local oscillators, JJ LO |
| Abstract |
Various applications in the field of terahertz technology are in urgent need of compact, wide-tunable solid-state continuous wave radiation sources with a moderate power. However, satisfactory solutions for the THz frequency range are scarce yet. Here we report on coherent radiation from a large planar array of Josephson junctions (JJs) in the frequency range between 0.1 and 0.3 THz. The external resonator providing the synchronization of JJ array is identified as a straight fragment of a single-strip-line containing the junctions themselves. We demonstrate a prototype of the quasioptical heterodyne receiver with the JJ array as a local oscillator and a hot-electron bolometer mixer. |
| 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 |
0953-2048 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
|
Serial |
1347 |
| Permanent link to this record |
| |
|
| |
| Author |
Murphy, A.; Semenov, A.; Korneev, A.; Korneeva, Y.; Gol'tsman, G.; Bezryadin, A. |
| Title |
Three temperature regimes in superconducting photon detectors: quantum, thermal and multiple phase-slips as generators of dark counts |
Type |
Journal Article |
| Year |
2015 |
Publication |
Sci. Rep. |
Abbreviated Journal |
Sci. Rep. |
| Volume |
5 |
Issue |
|
Pages |
10174 (1 to 10) |
| Keywords |
SPD, SSPD, SNSPD |
| Abstract |
We perform measurements of the switching current distributions of three w approximately 120 nm wide, 4 nm thick NbN superconducting strips which are used for single-photon detectors. These strips are much wider than the diameter of 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. At the highest temperatures the system enters a multiple phase-slip regime. In this range single phase-slips are unable to produce dark counts and the fluctuations in the switching current are reduced. |
| Address |
Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA |
| 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 |
2045-2322 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:25988591; PMCID:PMC4437302 |
Approved |
no |
| Call Number |
|
Serial |
1344 |
| Permanent link to this record |
