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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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| Author | Antipov, S.; Trifonov, A.; Krause, S.; Meledin, D.; Kaurova, N.; Rudzinski, M.; Desmaris, V.; Belitsky, V.; Goltsman, G. | ||||
| Title | Improved bandwidth of a 2 THz hot-electron bolometer heterodyne mixer fabricated on sapphire with a GaN buffer layer | Type | Journal Article | ||
| Year | 2019 | Publication | Supercond. Sci. Technol. | Abbreviated Journal | Supercond. Sci. Technol. |
| Volume | 32 | Issue | 7 | Pages |
075003 |
| Keywords | NbN HEB mixer, GaN buffer layer, sapphire substrate | ||||
| Abstract | We report on the signal-to-noise and gain bandwidth of a niobium nitride (NbN) hot-electron bolometer (HEB) mixer at 2 THz fabricated on a sapphire substrate with a GaN buffer layer. Two mixers with different DC properties and geometrical dimensions were studied and they demonstrated very close bandwidth performance. The signal-to-noise bandwidth is increased to 8 GHz in comparison to the previous results, obtained without a buffer-layer. The data were taken in a quasi-optical system with the use of the signal-to-noise method, which is close to the signal levels used in actual astrophysical observations. We find an increase of the gain bandwidth to 5 GHz. The results indicate that prior results obtained on a substrate of crystalline GaN can also be obtained on a conventional sapphire substrate with a few micron MOCVD-deposited GaN buffer-layer. | ||||
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| Publisher | IOP Publishing | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | Antipov_2019 | Serial | 1277 | ||
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| Author | Ren, Y.; Zhang, D. X.; Zhou, K. M.; Miao, W.; Zhang, W.; Shi, S. C.; Seleznev, V.; Pentin, I.; Vakhtomin, Y.; Smirnov, K. | ||||
| Title | 10.6 μm heterodyne receiver based on a superconducting hot-electron bolometer mixer and a quantum cascade laser | Type | Journal Article | ||
| Year | 2019 | Publication | AIP Advances | Abbreviated Journal | AIP Advances |
| Volume | 9 | Issue | 7 | Pages |
075307 |
| Keywords | NbN HEB mixers, QCL, IR | ||||
| Abstract | We report on the development of a heterodyne receiver at mid-infrared wavelength for high-resolution spectroscopy applications. The receiver employs a superconducting NbN hot electron bolometer as a mixer and a room temperature distributed feedback quantum cascade laser operating at 10.6 μm (28.2 THz) as a local oscillator. The stabilization of the heterodyne receiver has been achieved using a feedback loop controlling the output power of the laser. Improved Allan variance times as well as a double sideband receiver noise temperature of 5000 K and a noise bandwidth of 2.8 GHz of the receiver system are demonstrated. The work is supported in part by the National Key R&D Program of China under Grant 2018YFA0404701, by the CAS program under Grant QYZDJ-SSW-SLH043 and GJJSTD20180003, by the National Natural Science Foundation of China (NSFC) under Grant 11773083, by the “Hundred Talents Program” of the “Pioneer Initiative”, and in part by the CAS Key Lab for Radio Astronomy. |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 2158-3226 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1293 | |||
| Permanent link to this record | |||||
| Author | Baselmans, J. J. A.; Baryshev, A.; Reker, S. F.; Hajenius, M.; Gao, J. R.; Klapwijk, T. M.; Voronov, B.; Gol’tsman, G. | ||||
| Title | Influence of the direct response on the heterodyne sensitivity of hot electron bolometer mixers | Type | Journal Article | ||
| Year | 2006 | Publication | J. Appl. Phys. | Abbreviated Journal | J. Appl. Phys. |
| Volume | 100 | Issue | 8 | Pages |
084510 (1 to 7) |
| Keywords | NbN HEB mixers | ||||
| Abstract | We present a detailed experimental study of the direct detection effect in a small volume (0.15μm×1μm×3.5nm) quasioptical NbN phonon cooled hot electron bolometer mixer at 673GHz. We find that the small signal noise temperature, relevant for an astronomical observation, is 20% lower than the noise temperature obtained using 300 and 77K calibration loads. In a separate set of experiments we show that the direct detection effect is caused by a combination of bias current reduction when switching from the 77 to the 300K load in combination with the bias current dependence of the receiver gain. The bias current dependence of the receiver gain is shown to be mainly caused by the current dependence of the mixer gain. |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-8979 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1442 | |||
| Permanent link to this record | |||||
| Author | Zhang, W.; Miao, W.; Zhong, J. Q.; Shi, S. C.; Hayton, D. J.; Vercruyssen, N.; Gao, J. R.; Goltsman, G. N. | ||||
| Title | Temperature dependence of the receiver noise temperature and IF bandwidth of superconducting hot electron bolometer mixers | Type | Journal Article | ||
| Year | 2014 | Publication | Supercond. Sci. Technol. | Abbreviated Journal | Supercond. Sci. Technol. |
| Volume | 27 | Issue | 8 | Pages |
085013 (1 to 5) |
| Keywords | NbN HEB mixers | ||||
| Abstract | In this paper we study the temperature dependence of the receiver noise temperature and IF noise bandwidth of superconducting hot electron bolometer (HEB) mixers. Three superconducting NbN HEB devices of different transition temperatures (Tc) are measured at 0.85 THz and 1.4 THz at different bath temperatures (Tbath) between 4 K and 9 K. Measurement results demonstrate that the receiver noise temperature of superconducting NbN HEB devices is nearly constant for Tbath/Tc, less than 0.8, which is consistent with the simulation based on a distributed hot-spot model. In addition, the IF noise bandwidth appears independent of Tbath/Tc, indicating the dominance of phonon cooling in the investigated HEB devices. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0953-2048 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1358 | |||
| Permanent link to this record | |||||
| Author | Zhang, W.; Khosropanah, P.; Gao, J. R.; Kollberg, E. L.; Yngvesson, K. S.; Bansal, T.; Barends, R.; Klapwijk, T. M. | ||||
| Title | Quantum noise in a terahertz hot electron bolometer mixer | Type | Journal Article | ||
| Year | 2010 | Publication | Applied Physics Letters | Abbreviated Journal | Appl. Phys. Lett. |
| Volume | 96 | Issue | 11 | Pages |
111113-(1-3) |
| Keywords | HEB mixer, quantum limit, quantum noise, vacuum box, THz, Terahertz | ||||
| Abstract | We have measured the noise temperature of a single, sensitive superconducting NbN hot electron bolometer (HEB) mixer in a frequency range from 1.6 to 5.3 THz, using a setup with all the key components in vacuum. By analyzing the measured receiver noise temperature using a quantum noise (QN) model for HEB mixers, we confirm the effect of QN. The QN is found to be responsible for about half of the receiver noise at the highest frequency in our measurements. The beta-factor (the quantum efficiency of the HEB) obtained experimentally agrees reasonably well with the calculated value. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 624 | |||
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| Author | Shcherbatenko, M.; Tretyakov, I.; Lobanov, Yu.; Maslennikov, S. N.; Kaurova, N.; Finkel, M.; Voronov, B.; Goltsman, G.; Klapwijk, T. M. | ||||
| Title | Nonequilibrium interpretation of DC properties of NbN superconducting hot electron bolometers | Type | Journal Article | ||
| Year | 2016 | Publication | Appl. Phys. Lett. | Abbreviated Journal | |
| Volume | 109 | Issue | 13 | Pages |
132602 |
| Keywords | HEB mixer, contacts | ||||
| Abstract | We present a physically consistent interpretation of the dc electrical properties of niobiumnitride (NbN)-based superconducting hot-electron bolometer mixers, using concepts of nonequilibrium superconductivity. Through this, we clarify what physical information can be extracted from the resistive transition and the dc current-voltage characteristics, measured at suitably chosen temperatures, and relevant for device characterization and optimization. We point out that the intrinsic spatial variation of the electronic properties of disordered superconductors, such as NbN, leads to a variation from device to device. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1107 | |||
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| Author | Hübers, H.-W.; Semenov, A.; Holldack, K.; Schade, U.; Wüstefeld, G.; Gol’tsman, G. | ||||
| Title | Time domain analysis of coherent terahertz synchrotron radiation | Type | Journal Article | ||
| Year | 2005 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
| Volume | 87 | Issue | 18 | Pages |
184103 (1 to 3) |
| Keywords | NbN HEB mixers, applications | ||||
| Abstract | The time structure of coherent terahertz synchrotron radiation at the electron storage ring of the Berliner Elektronensynchrotron und Speicherring Gesellschaft has been analyzed with a fast superconducting hot-electron bolometer. The emission from a single bunch of electrons was found to last ∼1500ps at frequencies around 0.4THz, which is much longer than the length of an electron bunch in the time domain (∼5ps). It is suggested that this is caused by multiple reflections at the walls of the beam line. The quadratic increase of the power with the number of electrons in the bunch as predicted for coherent synchrotron radiation and the transition from stable to bursting radiation were determined from a single storage ring fill pattern of bunches with different populations. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1457 | |||
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| Author | Khosropanah, P.; Gao, J. R.; Laauwen, W. M.; Hajenius, M; Klapwijk, T. M. | ||||
| Title | Low noise NbN hot electron bolometer mixer at 4.3 THz | Type | Journal Article | ||
| Year | 2007 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
| Volume | 91 | Issue | Pages |
221111 (1 to 3) | |
| Keywords | NbN HEB mixers, NbN, contacts cleaning | ||||
| Abstract | We have studied the sensitivity of a superconducting NbN hot electron bolometer mixer integrated with a spiral antenna at 4.3 THz. Using hot/cold blackbody loads and a beam splitter all in vacuum, we measured a double sideband receiver noise temperature of 1300 K at the optimum local oscillator (LO) power of 330 nW, which is about 12 times the quantum noise (hnu/2kB). Our result indicates that there is no sign of degradation of the mixing process at the superterahertz frequencies. Moreover, a measurement method is introduced which allows us for an accurate determination of the sensitivity despite LO power fluctuations. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 584 | |||
| Permanent link to this record | |||||
| Author | Barends, R.; Hajenius, M.; Gao, J. R.; Klapwijk, T. M. | ||||
| Title | Current-induced vortex unbinding in bolometer mixers | Type | Journal Article | ||
| Year | 2005 | Publication | Applied Physics Letters | Abbreviated Journal | Appl. Phys. Lett. |
| Volume | 87 | Issue | Pages |
263506 (1 to 3) | |
| Keywords | HEB mixer numerical model, HEB model, IV-curves, vortex-antivortex, Berezinskii–Kosterlitz–Thouless theory, diffusion cooling channel, diffusion channel, distributed HEB model, distributed model, self-heating effect, temperature profile | ||||
| Abstract | We present a description of the current-voltage characteristics of hot electron bolometers in terms of the current-dependent intrinsic resistive transition of NbN films. We find that, by including this current dependence, we can correctly predict the complete current-voltage characteristics, showing excellent agreement with measurements for both low and high bias and for small as well as large devices. It is assumed that the current dependence is due to vortex-antivortex unbinding as described in the Berezinskii–Kosterlitz–Thouless theory. The presented approach will be useful in guiding device optimization for noise and bandwidth. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 604 | |||
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