Records |
Author |
Hübers, H.-W.; Schubert, J.; Krabbe, A.; Birk, M.; Wagner, G.; Semenov, A.; Gol’tsman, G.; Voronov, B.; Gershenzon, E. |
Title |
Parylene anti-reflection coating of a quasi-optical hot-electron-bolometric mixer at terahertz frequencies |
Type |
Journal Article |
Year |
2001 |
Publication |
Infrared Physics & Technology |
Abbreviated Journal |
Infrared Physics & Technology |
Volume |
42 |
Issue |
1 |
Pages |
41-47 |
Keywords |
NbN HEB mixers, anti-reflection coating |
Abstract |
Parylene C was investigated as anti-reflection coating for silicon at terahertz frequencies. Measurements with a Fourier-transform spectrometer show that the transmittance of pure silicon can be improved by about 30% when applying a layer of Parylene C with a quarter wavelength optical thickness. The 10% bandwidth of this coating extends from 1.5 to 3 THz for a center frequency of 2.3–2.5 THz, where the transmittance is constant. Heterodyne measurements demonstrate that the noise temperature of a hot-electron-bolometric mixer can be reduced significantly by coating the silicon lens of the hybrid antenna with a quarter wavelength Parylene C layer. Compared to the same mixer with an uncoated lens the improvement is about 30% at a frequency of 2.5 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 |
1350-4495 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference ![sorted by Conference field, descending order (down)](img/sort_desc.gif) |
|
Notes |
|
Approved |
no |
Call Number |
|
Serial |
1548 |
Permanent link to this record |
|
|
|
Author |
Antipov, S. V.; Svechnikov, S. I.; Smirnov, K. V.; Vakhtomin, Y. B.; Finkel, M. I.; Goltsman, G. N.; Gershenzon, E. M. |
Title |
Noise temperature of quasioptical NbN hot electron bolometer mixers at 900 GHz |
Type |
Journal Article |
Year |
2001 |
Publication |
Physics of Vibrations |
Abbreviated Journal |
Physics of Vibrations |
Volume |
9 |
Issue |
4 |
Pages |
242-245 |
Keywords |
NbN HEB mixers |
Abstract |
|
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 |
1069-1227 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference ![sorted by Conference field, descending order (down)](img/sort_desc.gif) |
|
Notes |
|
Approved |
no |
Call Number |
|
Serial |
1550 |
Permanent link to this record |
|
|
|
Author |
Svechnikov, S. I.; Antipov, S. V.; Vakhtomin, Y. B.; Goltsman, G. N.; Gershenzon, E. M.; Cherednichenko, S. I.; Kroug, M.; Kollberg, E. |
Title |
Conversion and noise bandwidths of terahertz NbN hot-electron bolometer mixers |
Type |
Journal Article |
Year |
2001 |
Publication |
Physics of Vibrations |
Abbreviated Journal |
Physics of Vibrations |
Volume |
9 |
Issue |
3 |
Pages |
205-210 |
Keywords |
NbN HEB mixers |
Abstract |
|
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 |
1069-1227 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference ![sorted by Conference field, descending order (down)](img/sort_desc.gif) |
|
Notes |
|
Approved |
no |
Call Number |
|
Serial |
1551 |
Permanent link to this record |
|
|
|
Author |
Cherednichenko, S.; Rönnung, F.; Gol'tsman, G.; Kollberg, E.; Winkler, D. |
Title |
YBa2Cu3O7−δ hot-electron bolometer mixer |
Type |
Journal Article |
Year |
2000 |
Publication |
Phys. C: Supercond. |
Abbreviated Journal |
Phys. C: Supercond. |
Volume |
341-348 |
Issue |
|
Pages |
2653-2654 |
Keywords |
YBCO HTS HEB mixers |
Abstract |
We present an investigation of hot-electron bolometric mixer based on YBa2Cu3O7−δ (YBCO) superconducting thin film. Mixer conversion loss, absorbed local oscillator power and intermediate frequency bandwidth was measured at the local oscillator frequency 600 GHz. The fabrication technique for nanoscale YBCO hot-electron bolometer (HEB) mixer integrated into planar antenna structure is described. |
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 |
0921-4534 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference ![sorted by Conference field, descending order (down)](img/sort_desc.gif) |
|
Notes |
|
Approved |
no |
Call Number |
|
Serial |
1552 |
Permanent link to this record |
|
|
|
Author |
Darula, Marian; Semenov, Alex D.; Hübers, Heinz-Wilhelm; Schubert, Josef |
Title |
Quasioptical high-Tc superconductor Josephson mixer at terahertz frequencies |
Type |
Abstract |
Year |
2000 |
Publication |
Proc. 11th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 11th Int. Symp. Space Terahertz Technol. |
Volume |
|
Issue |
|
Pages |
515 |
Keywords |
HTS Josephson mixers |
Abstract |
Mixers based on Josephson junctions from conventional superconductor materials have demonstrated excellent performance at subgap frequencies. The advantages of Josephson mixers are low optimal power of the local oscillator and large intermediate frequency bandwidth but their noise temperature increases dramatically at frequencies corresponding to the energy gap of the superconductor, which is typically below 1 THz for widely used materials. The large energy gap of oxide superconductors makes them promising candidates for development of terahertz Josephson mixers. Here we report on experimental study of the quasioptical mixer utilizing bicrystal Josephson junction from high-transition-temperature YBa 2 Cu 3 O 7-δ film. Junctions with a width of 2 µm were fabricated from 100 nm thick laser ablated films on bicrystal MgO substrates and had the and the J C R n product of about 2 mV at 4.2 K. The planar complementary logarithmic spiral antenna incorporated into co-planar waveguide was patterned from 200 nm thick gold film thermally evaporated in situ on top of the YBa 2 Cu 3 O 7-δ film. The mixer chip was clamped to the extended hemispherical silicon lens. Performance of the mixer was investigated at 4.5 K bath temperature. We used FIR laser as a local oscillator at frequencies 0.698 and 2.52 THz. System noise temperature (DSB) was determined from Y-factor measured with 300 K and 77 K loads. At 0.698 THz the lowest noise temperature 1750 K was observed when the mixer was biased with the fixed current to the region in the vicinity of either the first Shapiro step or the critical current. Between these two bias points the noise temperature increased to ≈ 20000 K. As function of the local oscillator power the noise temperature reached the minimum when the critical current was suppressed to the half of its equilibrium value. Power of the local oscillator absorbed by the mixer at optimal operation was of the order 100 nW. The present design of our antenna limits the upper operation frequency to the value of 1.8 THz. Nevertheless, we clearly observed Shapiro steps at the frequency 2.52 THz. Bearing in mind an improved design of the antenna, we estimate the 3000 K DSB noise temperature at this frequency. |
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 |
1555 |
Permanent link to this record |
|
|
|
Author |
Cherednichenko, S.; Rönnung, F.; Gol’tsman, G.; Kollberg, E.; Winkler, D. |
Title |
YBa2Cu3O7-δ hot-electron bolometer mixer at 0.6 THz |
Type |
Conference Article |
Year |
2000 |
Publication |
Proc. 11th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 11th Int. Symp. Space Terahertz Technol. |
Volume |
|
Issue |
|
Pages |
517-522 |
Keywords |
YBCO HTS HEB mixers |
Abstract |
We present an investigation of hot-electron bolometric mixer based on a YBa 2 Cu 3 O 7-δ (YBCO) superconducting thin film. Mixer conversion loss of –46 dB, absorbed local oscillator power and intermediate frequency bandwidth were measured at the local oscillator frequency 0.6 THz. The fabrication technique for nanoscale YBCO hot-electron bolometer (HEB) mixer integrated with a planar antenna structure is described. |
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 |
1556 |
Permanent link to this record |
|
|
|
Author |
Cherednichenko, S.; Kroug, M.; Yagoubov, P.; Merkel, H.; Kollberg, E.; Yngvesson, K. S.; Voronov, B.; Gol’tsman, G. |
Title |
IF bandwidth of phonon cooled HEB mixers made from NbN films on MgO substrates |
Type |
Conference Article |
Year |
2000 |
Publication |
Proc. 11th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 11th Int. Symp. Space Terahertz Technol. |
Volume |
|
Issue |
|
Pages |
219-227 |
Keywords |
NbN HEB mixers, cinversion gain bandwidth, IF bandwidth |
Abstract |
An investigation of gain and noise bandwidth of phonon-cooled hot-electron bolometric (HEB) mixers is presented. The radiation coupling to the mixers is quasioptical through either a spiral or twin-slot antenna. A maximum gain bandwidth of 4.8 GHz is obtained for mixers based on a 3.5 nm thin NbN film with Tc= 10 K. The noise bandwidth is 5.6 GHz, at the moment limited by parasitic elements in the, device mount fixture. At 0.65 THz the DSB receiver noise temperature is 700-800 К in the IF band 1-2 GHz, and 1150-2700 К in the band 3.5-7 GHz. |
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 |
1557 |
Permanent link to this record |
|
|
|
Author |
Semenov, A. D.; Gol’tsman, G. N. |
Title |
Nonthermal mixing mechanism in a diffusion-cooled hot-electron detector |
Type |
Journal Article |
Year |
2000 |
Publication |
J. Appl. Phys. |
Abbreviated Journal |
J. Appl. Phys. |
Volume |
87 |
Issue |
1 |
Pages |
502-510 |
Keywords |
NbN HEB mixers, nonthermal |
Abstract |
We present an analysis of a diffusion-cooled hot-electron detector fabricated from clean superconducting material with low transition temperature. The distinctive feature of a clean material, i.e., material with large electron mean free path, is a relatively weak inelastic electron scattering that is not sufficient for the establishment of an elevated thermodynamic electron temperature when the detector is subjected to irradiation. We propose an athermal model of a diffusion-cooled detector that relies on suppression of the superconducting energy gap by the actual dynamic distribution of excess quasiparticles. The resistive state of the device is caused by the electric field penetrating into the superconducting bridge from metal contacts. The dependence of the penetration length on the energy gap delivers the detection mechanism. The sources of the electric noise are equilibrium fluctuations of the number of thermal quasiparticles and frequency dependent shot noise. Using material parameters typical for A1, we evaluate performance of the device in the heterodyne regime at terahertz frequencies. Estimates show that the mixer may have a noise temperature of a few quantum limits and a bandwidth of a few tens of GHz, while the required local oscillator power is in the μW range due to ineffective suppression of the energy gap by quasiparticles with high energies. |
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 |
0021-8979 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference ![sorted by Conference field, descending order (down)](img/sort_desc.gif) |
|
Notes |
|
Approved |
no |
Call Number |
|
Serial |
1558 |
Permanent link to this record |
|
|
|
Author |
Smirnov, K. V.; Ptitsina, N. G.; Vakhtomin, Y. B.; Verevkin, A. A.; Gol’tsman, G. N.; Gershenzon, E. M. |
Title |
Energy relaxation of two-dimensional electrons in the quantum Hall effect regime |
Type |
Journal Article |
Year |
2000 |
Publication |
JETP Lett. |
Abbreviated Journal |
JETP Lett. |
Volume |
71 |
Issue |
1 |
Pages |
31-34 |
Keywords |
2DEG, GaAs/AlGaAs heterostructures |
Abstract |
The mm-wave spectroscopy with high temporal resolution is used to measure the energy relaxation times τe of 2D electrons in GaAs/AlGaAs heterostructures in magnetic fields B=0–4 T under quasi-equilibrium conditions at T=4.2 K. With increasing B, a considerable increase in τe from 0.9 to 25 ns is observed. For high B and low values of the filling factor ν, the energy relaxation rate τ −1e oscillates. The depth of these oscillations and the positions of maxima depend on the filling factor ν. For ν>5, the relaxation rate τ −1e is maximum when the Fermi level lies in the region of the localized states between the Landau levels. For lower values of ν, the relaxation rate is maximum at half-integer values of τ −1e when the Fermi level is coincident with the Landau level. The characteristic features of the dependence τ −1e (B) are explained by different contributions of the intralevel and interlevel electron-phonon transitions to the process of the energy relaxation of 2D electrons. |
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 |
0021-3640 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference ![sorted by Conference field, descending order (down)](img/sort_desc.gif) |
|
Notes |
http://jetpletters.ru/ps/899/article_13838.shtml (“Энергетическая релаксация двумерных электронов в области квантового эффекта Холла”) |
Approved |
no |
Call Number |
|
Serial |
1559 |
Permanent link to this record |
|
|
|
Author |
Gerecht, E.; Musante, C. F.; Zhuang, Y.; Yngvesson, K. S.; Gol’tsman, G. N.; Voronov, B. M.; Gershenzon, E. M. |
Title |
NbN hot electron bolometric mixerss—a new technology for low-noise THz receivers |
Type |
Journal Article |
Year |
1999 |
Publication |
IEEE Trans. Appl. Supercond. |
Abbreviated Journal |
IEEE Trans. Appl. Supercond. |
Volume |
47 |
Issue |
12 |
Pages |
2519-2527 |
Keywords |
NbN HEB mixers |
Abstract |
New advances in hot electron bolometer (HEB) mixers have recently resulted in record-low receiver noise temperatures at terahertz frequencies. We have developed quasi-optically coupled NbN HEB mixers and measured noise temperatures up to 2.24 THz, as described in this paper. We project the anticipated future performance of such receivers to have even lower noise temperature and local-oscillator power requirement as well as wider gain and noise bandwidths. We introduce a proposal for integrated focal plane arrays of HEB mixers that will further increase the detection speed of terahertz systems. |
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 |
1557-9670 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference ![sorted by Conference field, descending order (down)](img/sort_desc.gif) |
|
Notes |
|
Approved |
no |
Call Number |
|
Serial |
1560 |
Permanent link to this record |