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Miller, A. J., Lita, A. E., Calkins, B., Vayshenker, I., Gruber, S. M., & Nam, S. W. (2011). Compact cryogenic self-aligning fiber-to-detector coupling with losses below one percent. Opt. Express, 19(10), 9102–9110.
Abstract: We present a compact packaging technique for coupling light from a single-mode telecommunication fiber to cryogenic single-photon sensitive devices. Our single-photon detectors are superconducting transition-edge sensors (TESs) with a collection area only a factor of a few larger than the area of the fiber core which presents significant challenges to low-loss fiber-to-detector coupling. The coupling method presented here has low loss, cryogenic compatibility, easy and reproducible assembly and low component cost. The system efficiency of the packaged single-photon counting detectors is verified by the “triplet method†of power-source calibration along with the “multiple attenuator†method that produces a calibrated single-photon flux. These calibration techniques, when used in combination with through-wafer imaging and fiber back-reflection measurements, give us confidence that we have achieved coupling losses below 1 % for all devices packaged according to the self-alignment method presented in this paper.
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Hoevers, H. F. C., Bento, A. C., Bruijn, M. P., Gottardi, L., Korevaar, M. A. N., Mels, W. A., et al. (2000). Thermal fluctuation noise in a voltage biased superconducting transition edge thermometer. Appl. Phys. Lett., 77(26), 4421–4424.
Abstract: The current noise at the output of a microcalorimeter with a voltage biased superconducting transition edge thermometer is studied in detail. In addition to the two well-known noise sources: thermal fluctuation noise from the heat link to the bath and Johnson noise from the resistive thermometer, a third noise source strongly correlated with the steepness of the thermometer is required to fit the measured noise spectra. Thermal fluctuation noise, originating in the thermometer itself, fully explains the additional noise. A simple model provides quantitative agreement between the observed and calculated noise spectra for all bias points in the superconducting transition.
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Kooi, J. W. (2008). Advanced receivers for submillimeter and far infrared astronomy. Doctoral thesis, , .
Keywords: HEB, SIS, TES, NEP, noise temperature, IF bandwidth, waveguide, impedance, conversion gain, FTS, integrated array, stability, Allan variance, multi-layer antireflection coating
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Titova, N., Kardakova, A., Tovpeko, N., Ryabchun, S., Mandal, S., Morozov, D., et al. (2017). Superconducting diamond films as perspective material for direct THz detectors. In Proc. 28th Int. Symp. Space Terahertz Technol. (82).
Abstract: Superconducting films with a high resistivity in the normal state have established themselves as the best materials for direct THz radiation sensors, such as kinetic inductance detectors (KIDs) [1] and hot electron bolometers (nano-HEBs) [2]. The primary characteristics of the future instrument such as the sensitivity and the response time are determined by the material parameters such as the electron-phonon (e-ph) interaction time, the electron density and the resistivity of the material. For direct detectors, such as KIDs and nano-HEBs, to provide a high sensitivity and low noise one prefer materials with long e-ph relaxation times and low values of the electron density. As a potential material for THz radiation detection we have studied superconducting diamond films. A significant interest to diamond for the development of electronic devices is due to the evolution of its properties with the boron dopant concentration. At a high boron doping concentration, n B ~5·10 20 cm -3 , diamond has been reported to become a superconducting with T c depending on the doping level. Our previous study of energy relaxation in single-crystalline boron-doped diamond films epitaxially grown on a diamond shows a remarkably slow energy-relaxation at low temperatures. The electron-phonon cooling time varies from 400 ns to 700 ns over the temperature range 2.2 K to 1.7 K [3]. In superconducting materials such as Al and TiN, traditionally used in KIDs, the e-ph cooling times at 1.7 K correspond to ~20 ns [4] and ~100 ns [5], correspondingly. Such a noticeable slow e-ph relaxation in boron-doped diamond, in combination with a low value of carrier density (~10 21 cm -3 ) in comparison with typical metals (~10 23 cm -3 ) and a high normal state resistivity (~1500 μΩ·cm) confirms a potential of superconducting diamond for superconducting bolometers and resonator detectors. However, the price and the small substrate growth are of single crystal diamond limit practical applications of homoepitaxial diamond films. As an alternative way with more convenient technology, one can employ heteroepitaxial diamond films grown on large-size Si substrates. Here we report about measurements of e-ph cooling times in superconducting diamond grown on silicon substrate and discuss our expectations about the applicability of boron-doped diamond films to superconducting detectors. Our estimation of limit value of noise-equivalent power (NEP) and the energy resolution of bolometer made from superconducting diamond is order 10 -17 W/Hz 1/2 at 2 K and the energy resolution is of 0.1 eV that corresponds to counting single-photon up to 15 um. The estimation was obtained by using the film thickness of 70 nm and ρ ~ 1500 μΩ·cm, and the planar dimensions that are chosen to couple bolometer with 75 Ω log-spiral antenna. Although the value of NEP is far yet from what might like to have for certain astronomical applications, we believe that it can be improved by a suitable fabrication process. Also the direct detectors, based on superconducting diamond, will offer low noise performance at about 2 K, a temperature provided by inexpensive close-cycle refrigerators, which provides another practical advantage of development and application of these devices. [1] P.K. Day, et. al, Nature, 425, 817, 2003. [2] J. Wei, et al, Nature Nanotech., 3, 496, 2008. [3] A. Kardakova, et al, Phys. Rev. B, 93, 064506, 2016. [4] P. Santhanam and D. Prober, Phys. Rev. B, 29, 3733, 1984 [5] A. Kardakova, et al, Appl. Phys. Lett, vol. 103, p. 252602, 2013.
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Manus, M. K. M., Kash, J. A., Steen, S. E., Polonsky, S., Tsang, J. C., Knebel, D. R., et al. (2000). PICA: Backside failure analysis of CMOS circuits using picosecond imaging circuit analysis. Microelectronics Reliability, 40, 1353–1358.
Abstract: Normal operation of complementary metal-oxide semiconductor (CMOS) devices entails the emission of picosecond pulses of light, which can be used to diagnose circuit problems. The pulses that are observed from submicron sized field effect transistors (FETs) are synchronous with logic state switching. Picosecond Imaging Circuit Analysis (PICA), a new optical imaging technique combining imaging with timing, spatially resolves individual devices at the 0.5 micron level and switching events on a 10 picosecond timescale. PICA is used here for the diagnostics of failures on two VLSI microprocessors.
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Stellari, F., & Song, P. (2005). Testing of ultra low voltage CMOS microprocessors using the superconducting single-photon detector (SSPD). In Proc. 12th IPFA (2). IEEE.
Abstract: In F. Stellari and P. Song (2004) the authors have shown a comparison among different detectors used for diagnosing integrated circuits (ICs) by means of the PICA method. In their experiments they used two versions of the SSPD detector (p-SSPD is a prototype version, while c-SSPD is the first commercially available generation of the detector as presented in W. K. Lo et al. (2002), as well as the imaging detector (S-25 photo-multiplier tube (PMT) as discussed in W. G. McMullan (1987)) used in the conventional PICA technique. A microprocessor chip fabricated in a 0.13 μm 1.2 V technology is used to show that c-SSPD provides a significant reduction in acquisition time for the collection of optical waveforms from chips running at very low. In this paper, the authors summarize the main results.
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Steudle, G. A., Schietinger, S., Höckel, D., Dorenbos, S. N., Zadeh, I. E., Zwiller, V., et al. (2012). Measuring the quantum nature of light with a single source and a single detector. Phys. Rev. A, 86(5), 053814.
Abstract: An elementary experiment in optics consists of a light source and a detector. Yet, if the source generates nonclassical correlations such an experiment is capable of unambiguously demonstrating the quantum nature of light. We realized such an experiment with a defect center in diamond and a superconducting detector. Previous experiments relied on more complex setups, such as the Hanbury Brown and Twiss configuration, where a beam splitter directs light to two photodetectors, creating the false impression that the beam splitter is a fundamentally required element. As an additional benefit, our results provide a simplification of the widely used photon-correlation techniques.
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Hartogh, P., Jarchow, C., Lellouch, E., de Val-Borro, M., Rengel, M., Moreno, R., et al. (2010). Herschel/HIFI observations of Mars: First detection of O2 at submillimetre wavelengths and upper limits on HCl and H2O2. Astron. Astrophys., 521, L49.
Abstract: We report on an initial analysis of Herschel/HIFI observations of hydrogen chloride (HCl), hydrogen peroxide (H2O2), and molecular oxygen (O2) in the Martian atmosphere performed on 13 and 16 April 2010 (Ls ~ 77°). We derived a constant volume mixing ratio of 1400 ± 120 ppm for O2 and determined upper limits of 200 ppt for HCl and 2 ppb for H2O2. Radiative transfer model calculations indicate that the vertical profile of O2 may not be constant. Photochemical models determine the lowest values of H2O2 to be around Ls ~ 75° but overestimate the volume mixing ratio compared to our measurements.
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Tretyakov, I., Shurakov, A., Perepelitsa, A., Kaurova, N., Svyatodukh, S., Zilberley, T., et al. (2019). Silicon room temperature IR detectors coated with Ag2S quantum dots. In Proc. IWQO (pp. 369–371).
Abstract: For decades silicon has been the chief technological semiconducting material of modern microelectronics. Application of silicon detectors in optoelectronic devices are limited to the visible and near infrared ranges, due to their transparency for radiation with a wavelength higher than 1.1 μm. The expansion Si absorption towards longer wave lengths is a considerable interest to optoelectronic applications. In this work we present an elegant and effective solution to this problem using Ag2S quantum dots, creating impurity states in Si to cause sub-band gap photon absorption. The sensitivity of room temperature zero-bias Si_Ag2S detectors, which we obtained is 1011 cmHzW . Given the variety of QDs parameters such as: material, dimensions, our results open a path towards the future study and development of Si detectors for technological applications.
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Samsonova, A., Zolotov, P., Baeva, E., Lomakin, A., Titova, N., Kardakova, A., et al. (2021). Signatures of surface magnetic disorder in thin niobium films. IEEE Trans. Appl. Supercond., , 1.
Abstract: We present our studies on the evolution of the normal and superconducting properties with thickness of thin Nb films with a low level of non-magnetic disorder (kFl 150 for the thickest film in the set). The analysis of the superconducting behavior points to the presence of magnetic moments, hidden in the native oxide on the surface of Nb films. Using the Abrikosov-Gorkov theory, we obtain the density of surface magnetic moments of 1013 cm-2, which is in agreement with the previously reported data for Nb films.
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