|
|
Blagosklonskaya, L. E., Gershenzon, E. M., Gol’tsman, G. N., & Elant’ev, A. I. (1978). Effect of a strong magnetic field on the spectrum of donors in InSb. Sov. Phys. Semicond., 11(12), 1395–1397.
|
|
|
|
Merkel, H. F., Yagoubov, P. A., Kroug, M., Khosropanah, P., Kollberg, E. L., Gol’tsman, G. N., et al. (1998). Noise temperature and absorbed LO power measurement methods for NbN phonon-cooled hot electron bolometric mixers at terahertz frequencies. In Proc. 28th European Microwave Conf. (Vol. 1, pp. 294–299).
Abstract: In this paper the absorbed LO power requirements and the noise performance of NbN based phonon-cooled hot electron bolometric (HEB) quasioptical mixers are investigated for RF frequencies in the 0.55-1.1 range The minimal measured DSB noise temperatures are about 500 K at 640 GHz, 600 K at 750 GHz, 850 K at 910 GHz and 1250 K at 1.1 THz. The increase in noise temperature at 1.1THz is attributed to water absorption. The absorbed LO power is measured using a calorimetric approach. The results are subsequently corrected for lattice heating. These values are compared to results of a novel one dimensional hot spot mixer models and to a more traditional isotherm method which tends to underestimate the absorbed LO power for small bias powers. Typically a LO power between 50nW and 100nW is needed to pump the device to the optimal operating point.
|
|
|
|
Huebers, H. - W., Semenov, A., Richter, H., Birk, M., Krocka, M., Mair, U., et al. (2003). Superconducting hot electron bolometer as mixer for far-infrared heterodyne receivers. In T. G. Phillips, & J. Zmuidzinas (Eds.), Proc. SPIE (Vol. 4855, pp. 395–401). Presented at the Society of Photo-Optical Instrumentation Engineers (SPIE) Conference, 4855. Tucson, USA: SPIE.
Abstract: Heterodyne receivers for applications in astronomy need quantum limited sensitivity. In instruments which are currently under development for SOFIA or Herschel superconducting hot electron bolometers (HEB) will be used to achieve this goal at frequencies above 1.4 THz. We present results of the development of a phonon-cooled NbN HEB mixer for GREAT, the German Receiver for Astronomy at Terahertz Frequencies, which will be flown aboard SOFIA. The mixer is a small superconducting bridge incorporated in a planar feed antenna and a hyperhemispherical lens. Mixers with logarithmic-spiral and double-slot feed antennas have been investigated with respect to their noise temperature, conversion loss, linearity and beam pattern. At 2.5 THz a double sideband noise temperature of 2200 K was achieved. The conversion loss was 17 dB. The response of the mixer was linear up to 400 K load temperature. The performance was verified by measuring an emission line of methanol at 2.5 THz. The measured linewidth is in good agreement with the linewidth deduced from pressure broadening measurements at millimeter wavelength. The results demonstrate that the NbN HEB is very well suited as a mixer for far-infrared heterodyne receivers.
|
|
|
|
Ozhegov, R. V., Gorshkov, K. N., Smirnov, K. V., Gol’tsman, G. N., Filippenko, L. V., & Koshelets, V. P. (2010). Terahertz imaging system based on superconducting integrated receiver. In Proc. 2-nd Int. Conf. Terahertz and Microwave radiation: Generation, Detection and Applications (pp. 20–22).
Abstract: The development of terahertz imaging instruments for security systems is on the cutting edge of terahertz technology. We are developing a THz imaging system based on a superconducting integrated receiver (SIR). An SIR is a new type of heterodyne receiver based on an SIS mixer integrated with a flux-flow oscillator (FFO) and a harmonic mixer which is used for phase-locking the FFO. Developing an array of SIRs would allow obtaining amplitude and phase characteristics of incident radiation in the plane of the receiver. Employing an SIR in an imaging system means building an entirely new instrument with many advantages compare to traditional systems: i) high temperature resolution, comparable to the best results for incoherent receivers; ii) high spectral resolution allowing spectral analysis of various substances; iii) the local oscillator frequency can be varied to obtain images at different frequencies, effectively providing “color” images; iv) since a heterodyne receiver preserves the phase of the radiation, it is possible to construct 3D images. The paper presents a prototype THz imaging system using an 1 pixel SIR. We have studied the dependence of the noise equivalent temperature difference (NETD) on the integration time and also possible ways of achieving best possible sensitivity. An NETD of 13 mK was obtained with an integration time of 1 sec a detection bandwidth of 4 GHz at a local oscillator frequency of 520 GHz. An important advantage of an FFO is its wide operation range: 300-700 GHz.
|
|
|
|
Verevkin, A., Slysz, W., Pearlman, A., Zhang, J., Sobolewski, R., Okunev, O., et al. (2003). Real-time GHz-rate counting of infrared photons using nanostructured NbN superconducting detectors. In CLEO/QELS (CThM8). Optical Society of America.
Abstract: We demonstrate that our ultrathin, nanometer-width NbN superconducting single-photon detectors are capable of above 1-GHz-frequency, real-time counting of near-infrared photons. The measured system jitter of the detector is below 15 ps.
|
|
|
|
Beck, M., Klammer, M., Rousseau, I., Gol’tsman, G. N., Diamant, I., Dagan, Y., et al. (2015). Probing superconducting gap dynamics with THz pulses. In CLEO (SM3H.3 (1 to 2)). Optical Society of America.
Abstract: We studied superconducting gap dynamics in a BCS superconductor NbN and electron doped cuprate superconductor PCCO following excitation with near-infrared (NIR) and narrow band THz pulses. Systematic studies on PCCO imply very selective electron-phonon coupling.
|
|
|
|
Huebers, H. - W., Schubert, J., Semenov, A., Gol’tsman, G. N., Voronov, B. M., Gershenzon, E. M., et al. (1999). NbN phonon-cooled hot-electron bolometer as a mixer for THz heterodyne receivers. In J. M. Chamberlain (Ed.), Proc. SPIE (Vol. 3828, pp. 410–416). Spie.
Abstract: We have investigated a phonon-cooled NbN hot electron bolometric (HEB) mixer in the frequency range from 0.7 THz to 5.2 THz. The device was a 3.5 nm thin film with an in- plane dimension of 1.7 X 0.2 micrometers 2 integrated in a complementary logarithmic spiral antenna. The measured DSB receiver noise temperatures are 1500 K, 2200 K, 2600 K, 2900 K, 4000 K, 5600 K and 8800 K. The sensitivity fluctuation, the long term stability, and the antenna pattern were measured and the suitability of the mixer for a practical heterodyne receiver is discussed.
|
|
|
|
Svechnikov, S. I., Finkel, M. I., Maslennikov, S. N., Vachtomin, Y. B., Smirnov, K. V., Seleznev, V. A., et al. (2006). Superconducting hot electron bolometer mixer for middle IR range. In Proc. 16th Int. Crimean Microwave and Telecommunication Technology (Vol. 2, pp. 686–687).
Abstract: The developed directly lens coupled hot electron bolometer (HEB) mixer was based on 5 nm superconducting NbN deposited on GaAs substrate. The layout of the structure, including 30x20 mcm^2 active area coupled with a 50 Ohm coplanar line, was patterned by photolithography. The responsivity of the mixer was measured in a direct detection mode in the 25-64 THz frequency range. The noise performance of the mixer and the directivity of the receiver were investigated in a heterodyne mode. A 10.6 mum wavelength CW CO2 laser was utilized as a local oscillator.
|
|
|
|
Kurochkin, V. L., Zverev, A. V., Kurochkin, Y. V., Ryabtsev, I. I., Neizvestnyi, I. G., Ozhegov, R. V., et al. (2015). Long-distance fiber-optic quantum key distribution using superconducting detectors. In Proc. Optoelectron. Instrum. (Vol. 51, pp. 548–552).
Abstract: This paper presents the results of experimental studies on quantum key distribution in optical fiber using superconducting detectors. Key generation was obtained on an experimental setup based on a self-compensation optical circuit with an optical fiber length of 101.1 km. It was first shown that photon polarization encoding can be used for quantum key distribution in optical fiber over a distance in excess of 300 km.
|
|
|
|
Pentin, I. V., Smirnov, A. V., Ryabchun, S. A., Gol’tsman, G. N., Vaks, V. L., Pripolzin, S. I., et al. (2011). Heterodyne source of THz range based on semiconductor superlattice multiplier. In IRMMW-THz (pp. 1–2).
Abstract: We present the results of our studies of the possibility of developing a heterodyne receiver incorporating a hot-electron bolometer mixer as the detector and a semiconductor superlattice multiplier driven by a reference synthesizer as the local oscillator. We observe that such a local oscillator offers enough power in the terahertz range to pump the HEB into the operating state.
|
|
|
|
Zhang, W., Li, N., Jiang, L., Ren, Y., Yao, Q. - J., Lin, Z. - H., et al. (2008). Dependence of noise temperature of quasi-optical superconducting hot-electron bolometer mixers on bath temperature and optical-axis displacement. In C. Zhang, & X. - C. Zhang (Eds.), Proc. SPIE (Vol. 6840, 684007 (1 to 8)). Spie.
Abstract: It is known that the increase of bath temperature results in the decrease of critical current of superconducting hot-electron bolometer (HEB) mixers owing to the depression of superconductivity, thus leading to the degradation of the mixer’s sensitivity. Here we report our study on the effect of bath temperature on the heterodyne mixing performance of quasi-optical superconducting NbN HEB mixers incorporated with a two-arm log-spiral antenna. The correlation between the bath temperature, critical current, LO power requirement and noise temperature is investigated at 0.5 THz. Furthermore, the heterodyne mixing performance of quasi-optical superconducting NbN HEB mixers is examined while there is an optical-axis displacement between the center of the extended hemispherical silicon lens and the superconducting NbN HEB device, which is placed on the back of the lens. Detailed experimental results and analysis are presented.
|
|
|
|
Zinoni, C., Alloing, B., Li, L. H., Marsili, F., Fiore, A., Lunghi, L., et al. (2007). Single-photonics at telecom wavelengths using nanowire superconducting single photon detectors. In CLEO/QELS (QTuF6 (1 to 2)). Optical Society of America.
Abstract: Novel single-photon detectors based on NbN superconducting nanostructures promise orders-of- magnitude improvement over InGaAs APDs. We demonstrate this improved performance for the first time by measuring the g(2)(τ) on single photon states produced by a quantum dot at telecom wavelength.
|
|
|
|
Vachtomin, Y. B., Antipov, S. V., Maslennikov, S. N., Smirnov, K. V., Polyakov, S. L., Zhang, W., et al. (2006). Quasioptical hot electron bolometer mixers based on thin NBN films for terahertz region. In Proc. 16th Int. Crimean Microwave and Telecommunication Technology (Vol. 2, pp. 688–689).
Abstract: Presented in this paper are the performances of HEB mixers based on 2-3.5 nm thick NbN films integrated with log-periodic spiral antenna. Double side-band receiver noise temperature values are 1300 K and 3100 K at 2.5 THz and at 3.8 THz, respectively. Mixer gain bandwidth is 5.2 GHz. Local oscillator power is 1-3 muW for mixers with different active area
|
|
|
|
Dauler, E. A., Kerman, A. J., Robinson, B. S., Yang, J. K. W., Voronov, B. M., Gol’tsman, G. N., et al. (2006). Achieving high counting rates in superconducting nanowire single-photon detectors. In CLEO/QELS (JTuD3 (1 to 2)). Optical Society of America.
Abstract: Kinetic inductance is determined to be the primary limitation to the counting rate of superconducting nanowire single-photon counters. Approaches for overcoming this limitation will be discussed.
|
|
|
|
Rosfjord, K. M., Yang, J. K. W., Dauler, E. A., Anant, V., Berggren, K. K., Kerman, A. J., et al. (2006). Increased detection efficiencies of nanowire single-photon detectors by integration of an optical cavity and anti-reflection coating. In CLEO/QELS (JTuF2 (1 to 2)).
Abstract: We fabricate and test superconducting NbN-nanowire single-photon detectors with an integrated optical cavity and anti-reflection coating. We design the cavity and coating such as to maximize absorption in the NbN film of the detector.
|
|
