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Author | González, F. J.; Boreman, G. D. | ||||
Title | Comparison of dipole, bowtie, spiral and log-periodic IR antennas | Type | Journal Article | ||
Year | 2005 | Publication | Infrared Physics & Technology | Abbreviated Journal | Inf Phys & Technol |
Volume | 46 | Issue | 5 | Pages | 418-428 |
Keywords | optical antennas; Microbolometer; Infrared antennas; Antenna efficiency; Antenna-coupled detectors | ||||
Abstract | Antenna-coupled microbolometers use planar lithographic antennas to couple infrared radiation into a bolometer with sub-micron dimensions. In this paper four different types of infrared antennas were fabricated on thin grounded-substrates and coupled to microbolometers. Dipole, bowtie, spiral and log-periodic IR antenna-coupled detectors were measured at 10.6 μm and their performance compared. A new method to calculate the radiation efficiency based on the spatial and angular response of infrared antennas is presented and used to evaluate their performance. The calculated radiation efficiency for the dipole, bowtie, spiral and log-periodic IR antennas was 20%, 37%, 25% and 46% respectively. A dipole-length study was performed and shows that the quasistatic value of the effective permittivity accurately describes the incident wavelength in the substrate at infrared frequencies for antennas on a thin substrate. | ||||
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Notes | Approved | no | |||
Call Number | RPLAB @ gujma @ | Serial | 739 | ||
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Author | Doerr, C.R.; Zhang, C.; Winzer, P.J. | ||||
Title | Monolithic InP multi-wavelength coherent receiver | Type | Conference Article | ||
Year | 2010 | Publication | Conference on optical fiber communication, collocated national fiber optic engineers conference | Abbreviated Journal | Conf. OFC/NFOEC |
Volume | Issue | Pages | 1-3 | ||
Keywords | InP balanced detector, waveguide grating, polarization splitter, from chiralphotonics | ||||
Abstract | We propose and demonstrate a novel four-channel monolithic polarization-diversity dual-quadrature coherent receiver with balanced detection in InP. It uses an interleave-chirped arrayed waveguide grating that acts simultaneously as a demultiplexer, 90° hybrid, and polarization splitter. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 851 | |||
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Author | Il'in, K. S.; Lindgren, M.; Currie, M. A.; Semenov, D.; Gol'tsman, G. N.; Sobolewski, Roman; Cherednichenko, S. I.; Gershenzon, E. M. | ||||
Title | Picosecond hot-electron energy relaxation in NbN superconducting photodetectors | Type | Journal Article | ||
Year | 2000 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 76 | Issue | 19 | Pages | 2752-2754 |
Keywords | NbN HEB detectors, two-temperature model, IF bandwidth | ||||
Abstract | We report time-resolved characterization of superconducting NbN hot-electron photodetectors using an electro-optic sampling method. Our samples were patterned into micron-size microbridges from 3.5-nm-thick NbN films deposited on sapphire substrates. The devices were illuminated with 100 fs optical pulses, and the photoresponse was measured in the ambient temperature range between 2.15 and 10.6 K (superconducting temperature transition TC). The experimental data agreed very well with the nonequilibrium hot-electron, two-temperature model. The quasiparticle thermalization time was ambient temperature independent and was measured to be 6.5 ps. The inelastic electron–phonon scattering time Ï„e–ph tended to decrease with the temperature increase, although its change remained within the experimental error, while the phonon escape time Ï„es decreased almost by a factor of two when the sample was put in direct contact with superfluid helium. Specifically, Ï„e–ph and Ï„es, fitted by the two-temperature model, were equal to 11.6 and 21 ps at 2.15 K, and 10(±2) and 38 ps at 10.5 K, respectively. The obtained value of Ï„e–ph shows that the maximum intermediate frequency bandwidth of NbN hot-electron phonon-cooled mixers operating at TC can reach 16(+4/–3) GHz if one eliminates the bolometric phonon-heating effect. | ||||
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ISSN | 0003-6951 | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 856 | |||
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Author | D. Henrich, L. Rehm S. Dörner, M. Hofherr, K. Il'in, A. Semenov, and M. Siegel | ||||
Title | Detection efficiency of a spiral-nanowire superconducting single-photon detector | Type | Journal Article | ||
Year | 2012 | Publication | Abbreviated Journal | ||
Volume | Issue | Pages | |||
Keywords | Critical current, Nanoscale devices, Superconducting photodetectors. | ||||
Abstract | We investigate the detection efficiency of a spiral layout of a Superconducting Nanowire Single-Photon Detector (SNSPD). The design is less susceptible to the critical current reduction in sharp turns of the nanowire than the conventional meander design. Detector samples with different nanowire width from 300 to 100 nm are patterned from a 4 nm thick NbN film deposited on sapphire substrates. The critical current IC at 4.2 K for spiral, meander, and simple bridge structures is measured and compared. On the 100 nm wide samples, the detection efficiency is measured in the wavelength range 400-1700 nm and the cut-off wavelength of the hot-spot plateau is determined. In the optical range, the spiral detector reaches a detection efficiency of 27.6%, which is ~1.5 times the value of the meander. In the infrared range the detection efficiency is more than doubled. | ||||
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Corporate Author | D. Henrich, L. Rehm S. Dörner, M. Hofherr, K. Il'in, A. Semenov, and M. Siegel | Thesis | |||
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Notes | Approved | no | |||
Call Number | RPLAB @ seleznev @ | Serial | 880 | ||
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Author | Cherednichenko, Sergey; Drakinskiy, Vladimir; Berg, Therese; Khosropanah, Pourya; Kollberg, Erik | ||||
Title | Hot-electron bolometer terahertz mixers for the Herschel Space Observatory | Type | Journal Article | ||
Year | 2008 | Publication | Review of Scientific Instruments | Abbreviated Journal | Rev. Sci. Instrum. |
Volume | 79 | Issue | Pages | 034501 | |
Keywords | HEB mixer, HEB detector, HEB direct detector, applications | ||||
Abstract | We report on low noise terahertz mixers(1.4–1.9THz) developed for the heterodyne spectrometer onboard the Herschel Space Observatory. The mixers employ double slot antenna integrated superconducting hot-electron bolometers (HEBs) made of thin NbN films. The mixer performance was characterized in terms of detection sensitivity across the entire rf band by using a Fourier transform spectrometer (from 0.5to2.5THz, with 30GHz resolution) and also by measuring the mixernoise temperature at a limited number of discrete frequencies. The lowest mixernoise temperature recorded was 750K [double sideband (DSB)] at 1.6THz and 950KDSB at 1.9THz local oscillator (LO) frequencies. Averaged across the intermediate frequency band of 2.4–4.8GHz, the mixernoise temperature was 1100KDSB at 1.6THz and 1450KDSB at 1.9THz LO frequencies. The HEB heterodyne receiver stability has been analyzed and compared to the HEB stability in the direct detection mode. The optimal local oscillator power was determined and found to be in a 200–500nW range. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 908 | |||
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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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Author | Shurakov, A.; Tong, Cheuk-yu E.; Grimes, P.; Blundell, R.; Golt'sman, G. | ||||
Title | A microwave reflection readout scheme for hot electron bolometric direct detector | Type | Journal Article | ||
Year | 2015 | Publication | IEEE Trans. THz Sci. Technol. | Abbreviated Journal | IEEE Trans. THz Sci. Technol. |
Volume | 5 | Issue | Pages | 81-84 | |
Keywords | HEB detectors | ||||
Abstract | In this paper, we propose and present data from a fast THz detector based on the repurpose of hot electron bolometer mixers (HEB) fabricated from superconducting NbN thinfilm. This detector is essentially a traditional NbN bolometer element that operates under the influence of a microwave pump. The in-jected microwave power serves the dual purpose of enhancing the detector sensitivity and reading out the impedance changes of the device in response to incidentTHz radiation. We have measured an optical Noise Equivalent Power of 4 pW/ Hz for our detector at a bath temperature of 4.2 K. The measurement frequency was 0.83 THz and the modulation frequency was 1.48 kHz. The readout scheme is versatile and facilitates both high-speed operation as well as multi-pixel applications. |
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Notes | Approved | no | |||
Call Number | RPLAB @ atomics90 @ | Serial | 950 | ||
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Author | Seliverstov, S.; Maslennikov, S.; Ryabchun, S.; Finkel, M.; Klapwijk, T. M.; Kaurova, N.; Vachtomin, Yu.; Smirnov, K.; Voronov, B.; Goltsman, G. | ||||
Title | Fast and sensitive terahertz direct detector based on superconducting antenna-coupled hot electron bolometer | Type | Journal Article | ||
Year | 2015 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
Volume | 25 | Issue | 3 | Pages | 2300304 |
Keywords | HEB detector responsivity, HEB model, numerical calculations, numerical model | ||||
Abstract | We characterize superconducting antenna-coupled hot-electron bolometers for direct detection of terahertz radiation operating at a temperature of 9.0 K. The estimated value of responsivity obtained from lumped-element theory is strongly different from the measured one. A numerical calculation of the detector responsivity is developed, using the Euler method, applied to the system of heat balance equations written in recurrent form. This distributed element model takes into account the effect of nonuniform heating of the detector along its length and provides results that are in better agreement with the experiment. At a signal frequency of 2.5 THz, the measured value of the optical detector noise equivalent power is 2.0 × 10-13 W · Hz-0.5. The value of the bolometer time constant is 35 ps. The corresponding energy resolution is about 3 aJ. This detector has a sensitivity similar to that of the state-of-the-art sub-millimeter detectors operating at accessible cryogenic temperatures, but with a response time several orders of magnitude shorter. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 953 | |||
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Author | Jiang, Leaf A.; Luu, Jane X. | ||||
Title | Heterodyne detection with a weak local oscillator | Type | Journal Article | ||
Year | 2008 | Publication | Appl. Opt. | Abbreviated Journal | Appl. Opt. |
Volume | 47 | Issue | 10 | Pages | 1486-1503 |
Keywords | weak local oscillator, weak LO, photon-counting detector, photon-counting mixer, counter detector, counter mixer, PD mixer, PCD mixer | ||||
Abstract | eterodyne detection in the limit of weak (a few photons) local oscillator and signal power levels has been largely neglected in the past, as authors almost always assumed that the noise was dominated by the shot noise from a strong local oscillator. We present the theory for heterodyne detection of diffuse and specular targets at arbitrary power levels, including the case where the local oscillator power is only a few photons per coherent integration period. The theory was tested with experimental results, and was found to show good agreement. We show how to interpret the power spectral density of the heterodyne signal and how to determine the optimal number of signal and local oscillator photons per coherent integration. | ||||
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Call Number | Serial | 979 | |||
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Author | Palma, F.; Teppe, F.; Fatimy, A. E.; Green, R.; Xu, J.; Vachontin, Y.; Tredicucci, A.; Goltsman, G.; Knap, W. | ||||
Title | THz communication system based on a THz quantum cascade laser and a hot electron bolometer | Type | Conference Article | ||
Year | 2010 | Publication | 35th Int. Conf. Infrared, Millimeter, and Terahertz Waves | Abbreviated Journal | 35th Int. Conf. Infrared, Millimeter, and Terahertz Waves |
Volume | Issue | Pages | 11623798 (1 to 2) | ||
Keywords | QCL, HEB detector | ||||
Abstract | We present the experimental study of the direct emission – detection system based on the THz Quantum Cascade Laser as a source and Hot Electron Bolometer (HEB) detector – in view of its application as an optical communication system. We show that the system can efficiently transmit the QCL Terahertz pulses. We estimate the maximal modulation speed of the system to be about several GHz and show that it is limited only by the QCL pulse power supply, detector amplifier and connection line/wires parameters. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 1391 | |||
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