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| Author | Gerecht, E.; Musante, C. F.; Wang, Z.; Yngvesson, K. S.; Waldman, J.; Gol'tsman, G. N.; Yagoubov, P. A.; Svechnikov, S. I.; Voronov, B. M.; Cherednichenko, S. I.; Gershenzon, E. M. | ||||
Title  |
NbN hot electron bolometric mixer for 2.5 THz: the phonon cooled version | Type | Conference Article | ||
| Year | 1997 | Publication | Proc. 8th Int. Symp. Space Terahertz Technol. | Abbreviated Journal | Proc. 8th Int. Symp. Space Terahertz Technol. |
| Volume | Issue | Pages | 258-271 | ||
| Keywords | NbN HEB mixers | ||||
| Abstract | We describe an investigation of a NbN HEB mixer for 2.5 THz. NbN HEBs are phonon-cooled de-. vices which are expected, according to theory, to achieve up to 10 GHz IF conversion gain bandwidth. We have developed an antenna coupled device using a log-periodic antenna and a silicon lens. We have demon- strated that sufficient LO power can be coupled to the device in order to bring it to the optimum mixer oper- ating point. The LO power required is less than 1 microwatts as measured directly at the device. We also describe the impedance characteristics of NbN devices and compare them with theory. The experimental results agree with theory except for the imaginary part of the impedance at very low frequencies as was demonstrated by other groups. | ||||
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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1605 | |||
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| Author | Baselmans, J. J. A.; Hajenius, M.; Gao, J. R.; Baryshev, A.; Kooi, J.; Klapwijk, T. M.; Voronov, B.; de Korte, P.; Gol'tsman, G. | ||||
| Title |
NbN hot electron bolometer mixers: sensitivity, LO power, direct detection and stability | Type | Journal Article | ||
| Year | 2005 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
| Volume | 15 | Issue | 2 | Pages | 484-489 |
| Keywords | HEB mixers, direct detection effect, stability, Allan variance | ||||
| Abstract | We demonstrate that the performance of NbN lattice cooled hot electron bolometer mixers depends strongly on the interface quality between the bolometer and the contact structure. Both the receiver noise temperature and the gain bandwidth can be improved by a factor of 2 by cleaning the interface and adding an additional superconducting interlayer to the contact pad. Using this we obtain a double sideband receiver noise temperature of 950 K at 2.5 THz and 4.3 K, using a 0.4/spl times/4 /spl mu/m HEB mixer with a spiral antenna. At the same bias point, we obtain an IF gain bandwidth of 6 GHz. To comply with current demands on THz mixers for use in space based receivers we reduce the device size to 0.15/spl times/1 /spl mu/m and use a twin slot antenna. We report measurements of the noise temperature, LO power requirement, stability and the direct detection effect, using a mixer with a 1.6 THz twin slot antenna and a 1.462 THz solid state LO source with calibrated output power. | ||||
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| ISSN | 1051-8223 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 546 | |||
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| Author | Gao, J. R.; Hajenius, M.; Baselmans, J. J. A.; Klapwijk, T. M.; de Korte, P. A. J.; Voronov, B.; Gol'tsman, G. | ||||
| Title |
NbN hot electron bolometer mixers with superior performance for space applications | Type | Conference Article | ||
| Year | 2004 | Publication | Proc. Int. workshop on low temp. electronics | Abbreviated Journal | Proc. Int. workshop on low temp. electronics |
| Volume | Issue | Pages | 11-17 | ||
| Keywords | NbN HEB mixers, applications | ||||
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| Publisher | Place of Publication | Noordwijk | Editor | Armandillo, E.; Leone, B. | |
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| Area | Expedition | Conference | International workshop on low temperature electronics- WOLTE 6 - Noordwijk | ||
| Notes | Approved | no | |||
| Call Number | Serial | 1496 | |||
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| Author | Tretyakov, I. V.; Ryabchun, S. A.; Maslennikov, S. N.; Finkel, M. I.; Kaurova, N. S.; Seleznev, V. A.; Voronov, B. M.; Gol'tsman, G.N. | ||||
| Title |
NbN HEB mixer: fabrication, noise temperature reduction and characterization | Type | Conference Article | ||
| Year | 2008 | Publication | Proc. Basic problems of superconductivity | Abbreviated Journal | |
| Volume | Issue | Pages | |||
| Keywords | HEB, mixer, noise temperature, conversion gain bandwidth | ||||
| Abstract | We demonstrate that in the terahertz region superconducting hot-electron mixers offer the lowest noise temperature, opening the possibility of using HTS's in the future to fabricate these devices. Specifically, a noise temperature of 950 K was measured for the receiver operating at 2.5 THz with a NbN HEB mixer, and a gain bandwidth of 6 GHz was measured at 300 GHz near Tc for the same mixer. | ||||
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| Publisher | Place of Publication | Moscow-Zvenigorod | Editor | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 591 | |||
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| 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. |
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| Corporate Author | Thesis | Ph.D. thesis | |||
| Publisher | Chalmers University of Technology | Place of Publication | Göteborg | Editor | |
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| Notes | Approved | no | |||
| Call Number | Serial | 910 | |||
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