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| Author | Pentin, I. V.; Smirnov, A. V.; Ryabchun, S. A.; Ozhegov, R. V.; Gol’tsman, G. N.; Vaks, V. L.; Pripolzin, S. I.; Pavel’ev, D. G.; Koshurinov, Y. I.; Ivanov, A. S. | ||||
Title  |
Semiconducting superlattice as a solid-state terahertz local oscillator for NbN hot-electron bolometer mixers | Type | Journal Article | ||
| Year | 2012 | Publication | Tech. Phys. | Abbreviated Journal | Tech. Phys. |
| Volume | 57 | Issue | 7 | Pages | 971-974 |
| Keywords | semiconducting superlattice frequency multiplier, NbN HEB mixers | ||||
| Abstract | We present the results of our studies of the semiconducting superlattice (SSL) frequency multiplier and its application as part of the solid state local oscillator (LO) in the terahertz heterodyne receiver based on a NbN hot-electron bolometer (HEB) mixer. We show that the SSL output power level increases as the ambient temperature is lowered to 4.2 K, the standard HEB operation temperature. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1063-7842 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1378 | |||
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| Author | Tretyakov, I. V.; Anfertyev, V. A.; Revin, L. S.; Kaurova, N. S.; Voronov, B. M.; Vaks, V. L.; Goltsman, G. N. | ||||
| Title |
Sensitivity and resolution of a heterodyne receiver based on the NbN HEB mixer with a quantum-cascade laser as a local oscillator | Type | Journal Article | ||
| Year | 2018 | Publication | Radiophys. Quant. Electron. | Abbreviated Journal | Radiophys. Quant. Electron. |
| Volume | 60 | Issue | 12 | Pages | 988-992 |
| Keywords | NbN HEB mixer | ||||
| Abstract | We present the results of experimental studies of the basic characteristics and operation features of a terahertz heterodyne detector based on the superconducting NbN HEB mixer and a quantum cascade laser as a local oscillator operating at a frequency of 2.02 THz. The measured noise temperature of such a mixer amounted to 1500 K. The spectral resolution of the detector is determined by the width of the local-oscillator spectral line whose measured value does not exceed 1 MHz. The quantum-cascade laser could be linearly tuned with respect to frequency with the coefficient 7.2 MHz/mA within the limits of the current oscillation bandwidth. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0033-8443 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1307 | |||
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| Author | Gol'tsman, G.; Jacobsson, S.; Ekstrom, H.; Karasik, B.; Kollberg, E.; Gershenzon, E. | ||||
| Title |
Slot-line tapered antenna with NbN hot electron mixer for 300-360 GHz operation | Type | Conference Article | ||
| Year | 1994 | Publication | Proc. 5th Int. Symp. Space Terahertz Technol. | Abbreviated Journal | Proc. 5th Int. Symp. Space Terahertz Technol. |
| Volume | Issue | Pages | 209-213a | ||
| Keywords | NbN HEB mixers | ||||
| Abstract | NbN hot-electron mixers combined with slot-line tapered antennas on Si wdnitride membranes had been fabricated. Several strips of 1 gm wide and 5 tan long made from 100 A NbN film are inserted into the slot antenna. IV-curves under local oscillator power in 300-350 GHz frequency range and conversion gain dependencies on intermediate fre- quency in the 0.1-1 GHz range are measured and compared with that for 100 GHz frequency band. Our results show that pumped IV-curves and intermediate frequency bands are different for 100 GHz and 300 GHz frequency ranges. The interpretation exploits the fact that for the lowest radiation frequency the superconducting energy gap is larger than the radiation quantum energy while they are comparable at the higher frequency. Tha results show that such mixers have good perspectives for terahertz receiving technology. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1643 | |||
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| Author | Cavalié, T.; Feuchtgruber, H.; Lellouch, E.; de Val-Borro, M.; Jarchow, C.; Moreno, R.; Hartogh, P.; Orton, G.; Greathouse, T. K.; Billebaud, F.; Dobrijevic, M.; Lara, L. M.; González, A.; Sagawa, H. | ||||
| Title |
Spatial distribution of water in the stratosphere of Jupiter from Herschel HIFI and PACS observations | Type | Journal Article | ||
| Year | 2013 | Publication | Astron. Astrophys. | Abbreviated Journal | |
| Volume | 553 | Issue | Pages | A21 (1 to 16) | |
| Keywords | HEB mixer applications, HIFI, Herschel | ||||
| Abstract | Context. In the past 15 years, several studies suggested that water in the stratosphere of Jupiter originated from the Shoemaker-Levy 9 (SL9) comet impacts in July 1994, but a direct proof was missing. Only a very sensitive instrument observing with high spectral/spatial resolution can help to solve this problem. This is the case of the Herschel Space Observatory, which is the first telescope capable of mapping water in Jupiter's stratosphere. Aims. We observed the spatial distribution of the water emission in Jupiter's stratosphere with the Heterodyne Instrument for the Far Infrared (HIFI) and the Photodetector Array Camera and Spectrometer (PACS) onboard Herschel to constrain its origin. In parallel, we monitored Jupiter's stratospheric temperature with the NASA Infrared Telescope Facility (IRTF) to separate temperature from water variability. Methods. We obtained a 25-point map of the 1669.9 GHz water line with HIFI in July 2010 and several maps with PACS in October 2009 and December 2010. The 2010 PACS map is a 400-point raster of the water 66.4 μm emission. Additionally, we mapped the methane ν4 band emission to constrain the stratospheric temperature in Jupiter in the same periods with the IRTF. Results. Water is found to be restricted to pressures lower than 2 mbar. Its column density decreases by a factor of 2–3 between southern and northern latitudes, consistently between the HIFI and the PACS 66.4 μm maps. We infer that an emission maximum seen around 15 °S is caused by a warm stratospheric belt detected in the IRTF data. Conclusions. Latitudinal temperature variability cannot explain the global north-south asymmetry in the water maps. From the latitudinal and vertical distributions of water in Jupiter's stratosphere, we rule out interplanetary dust particles as its main source. Furthermore, we demonstrate that Jupiter's stratospheric water was delivered by the SL9 comet and that more than 95% of the observed water comes from the comet according to our models. |
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| Notes | Approved | no | |||
| Call Number | Serial | 1085 | |||
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| Author | Zhang, W.; Miao, W.; Yao, Q. J.; Lin, Z. H.; Shi, S. C.; Gao, J. R.; Goltsman, G. N. | ||||
| Title |
Spectral response and noise temperature of a 2.5 THz spiral antenna coupled NbN HEB mixer | Type | Journal Article | ||
| Year | 2012 | Publication | Phys. Procedia | Abbreviated Journal | Phys. Procedia |
| Volume | 36 | Issue | Pages | 334-337 | |
| Keywords | NbN HEB mixer | ||||
| Abstract | We report on a 2.5 THz spiral antenna coupled NbN hot electron bolometer (HEB) mixers, fabricated with in-situ process. The receiver noise temperature with lowest value of 1180 K is in good agreement with calculated quantum efficiency factor as a function of bias voltage. In addition, the measured spectral response of the spiral antenna coupled NbN HEB mixer shows broad frequency coverage of 0.8-3 THz, and corrected response for optical losses, FTS, and coupling efficiency between antenna and bolometer falls with frequency due to diffraction-limited beam of lens/antenna combination. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1875-3892 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1381 | |||
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| Author | Burke, P. J.; Schoelkopf, R. J.; Prober, D. E.; Skalare, A.; Karasik, B. S.; Gaidis, M. C.; McGrath, W. R.; Bumble, B.; Leduc, H. G. | ||||
| Title |
Spectrum of thermal fluctuation noise in diffusion and phonon cooled hot-electron mixers | Type | Journal Article | ||
| Year | 1998 | Publication | Applied Physics Letters | Abbreviated Journal | Appl. Phys. Lett. |
| Volume | 72 | Issue | 12 | Pages | 1516-1518 |
| Keywords | HEB mixer; thermal fluctuation noise; TFN | ||||
| Abstract | A systematic study of the intermediate frequency noise bandwidth of Nb thin-film superconducting hot-electron bolometers is presented. We have measured the spectrum of the output noise as well as the conversion efficiency over a very broad intermediate frequency range (from 0.1 to 7.5 GHz) for devices varying in length from 0.08 μm to 3 μm. Local oscillator and rf signals from 8 to 40 GHz were used. For a device of a given length, the spectrum of the output noise and the conversion efficiency behave similarly for intermediate frequencies less than the gain bandwidth, in accordance with a simple thermal model for both the mixing and thermal fluctuation noise. For higher intermediate frequencies the conversion efficiency decreases; in contrast, the noise decreases but has a second contribution which dominates at higher frequency. The noise bandwidth is larger than the gain bandwidth, and the mixer noise is low, between 120 and 530 K (double side band). | ||||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ gujma @ | Serial | 760 | ||
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| Author | Maslennikov, S. N.; Finkel, M. I.; Antipov, S. V.; Polyakov, S. L.; Zhang, W.; Ozhegov, R.; Vachtomin, Yu. B.; Svechnikov, S. I.; Smirnov, K. V.; Korotetskaya, Yu. P.; Kaurova, N. S.; Gol'tsman, G. N.; Voronov, B. M. | ||||
| Title |
Spiral antenna coupled and directly coupled NbN HEB mixers in the frequency range from 1 to 70 THz | Type | Conference Article | ||
| Year | 2006 | Publication | Proc. 17th Int. Symp. Space Terahertz Technol. | Abbreviated Journal | Proc. 17th Int. Symp. Space Terahertz Technol. |
| Volume | Issue | Pages | 177-179 | ||
| Keywords | directly coupled NbN HEB mixers | ||||
| Abstract | We investigate both antenna coupled and directly coupled HEB mixers at several LO frequencies within the range of 2.5 THz to 70 THz. H20 (2.5+10.7 THz), and CO2 (30 THz) gas discharge lasers are used as the local oscillators. The noise temperature of antenna coupled mixers is measured at LO frequencies of 2.5 THz, 3.8 THz, and 30 THz. The results for both antenna coupled and directly coupled mixer types are compared. The devices with in—plane dimensions of 5x5 ,um 2 are pumped by LO radiation at 10.7 THz. The directly coupled HEB demonstrates nearly flat dependence of responsivity on frequency in the range of 25+64 THz. | ||||
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| Publisher | Place of Publication | Paris, France | Editor | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 386 | |||
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| Author | Svechnikov, S.; Gol'tsman, G.; Voronov, B.; Yagoubov, P.; Cherednichenko, S.; Gershenzon, E.; Belitsky, V.; Ekstrom, H.; Kollberg, E.; Semenov, A.; Gousev, Y.; Renk, K. | ||||
| Title |
Spiral antenna NbN hot-electron bolometer mixer at submm frequencies | Type | Journal Article | ||
| Year | 1997 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
| Volume | 7 | Issue | 2 | Pages | 3395-3398 |
| Keywords | NbN HEB mixers | ||||
| Abstract | We have studied the phonon-cooled hot-electron bolometer (HEB) as a quasioptical mixer based on a spiral antenna designed for the 0.3-1 THz frequency band and fabricated on sapphire and high resistivity silicon substrates. HEB devices were produced from superconducting 3.5-5 nm thick NbN films with a critical temperature 10-12 K and a critical current density of approximately 10/sup 7/ A/cm/sup 2/ at 4.2 K. For these devices we reached a DSB receiver noise temperature below 1500 K, a total conversion loss of L/sub t/=16 dB in the 500-700 GHz frequency range, an IF bandwidth of 3-4 GHz and an optimal LO absorbed power of /spl sime/4 /spl mu/W. We experimentally analyzed various contributions to the conversion loss and obtained an RF coupling factor of about 5 dB, internal mixer loss of 10 dB and IF mismatch of 1 dB. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1051-8223 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1597 | |||
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| Author | Ryabchun, Sergey; Tong, Cheuk-yu Edward; Blundell, Raymond; Kimberk, Robert; Gol’tsman, Gregory | ||||
| Title |
Stabilisation of a terahertz hot-electron bolometer mixer with microwave feedback control | Type | Conference Article | ||
| Year | 2007 | Publication | Proc. 18th Int. Symp. Space Terahertz Technol. | Abbreviated Journal | Proc. 18th Int. Symp. Space Terahertz Technol. |
| Volume | Issue | Pages | 193-198 | ||
| Keywords | waveguide NbN HEB mixers, Allan variance, stability | ||||
| Abstract | We report on implementation of microwave feedback control loop to stabilise the performance of an HEB mixer receiver. It is shown that the receiver sensitivity increases by a factor of 4 over a 16-minute scan, and the corresponding Allan time increases up to 10 seconds, as opposed to an open loop value of 1 second. Our experiments also demonstrate that the receiver sensitivity is limited by the intermediate frequency chain. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1421 | |||
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| Author | Kooi, J. W.; Baselmans, J. J. A.; Baryshev, A.; Schieder, R.; Hajenius, M.; Gao, J.R.; Klapwijk, T. M.; Voronov, B.; Gol’tsman, G. | ||||
| Title |
Stability of heterodyne terahertz receivers | Type | Journal Article | ||
| Year | 2006 | Publication | J. Appl. Phys. | Abbreviated Journal | J. Appl. Phys. |
| Volume | 100 | Issue | 6 | Pages | 064904 (1 to 9) |
| Keywords | NbN HEB mixers | ||||
| Abstract | In this paper we discuss the stability of heterodyne terahertz receivers based on small volume NbN phonon cooled hot electron bolometers (HEBs). The stability of these receivers can be broken down in two parts: the intrinsic stability of the HEB mixer and the stability of the local oscillator (LO) signal injection scheme. Measurements show that the HEB mixer stability is limited by gain fluctuations with a 1∕f spectral distribution. In a 60MHz noise bandwidth this results in an Allan variance stability time of ∼0.3s. Measurement of the spectroscopic Allan variance between two intermediate frequency (IF) channels results in a much longer Allan variance stability time, i.e., 3s between a 2.5 and a 4.7GHz channel, and even longer for more closely spaced channels. This implies that the HEB mixer 1∕f noise is strongly correlated across the IF band and that the correlation gets stronger the closer the IF channels are spaced. In the second part of the paper we discuss atmospheric and mechanical system stability requirements on the LO-mixer cavity path length. We calculate the mixer output noise fluctuations as a result of small perturbations of the LO-mixer standing wave, and find very stringent mechanical and atmospheric tolerance requirements for receivers operating at terahertz frequencies. | ||||
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| ISSN | 0021-8979 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1444 | |||
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