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Jiang, L. A., & Luu, J. X. (2008). Heterodyne detection with a weak local oscillator. Appl. Opt., 47(10), 1486–1503.
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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Semenov, A. V., Devyatov, I. A., Ryabchun, S. A., Maslennikov, S. N., Maslennikova, A. S., Larionov, P. A., et al. (2011). Absorption of terahertz electromagnetic radiation in dirty superconducting film at arbitrary type of the spectral functions. Rus. J. Radio Electron., (10).
Abstract: A problem of absorption of high-frequency electromagnetic field in dirty superconductor is treated within Keldysh technic. Expression for the source term in the kinetic equation for quasiparticle distribution function is derived. The result is significant for deriving a consistent microscopic theory of superconducting detectors for terahertz frequency range, perspective detectors on kinetic inductance of current-biased superconducting strip and on Josephson inductance of tunnel.
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Lieberzeit, P., Afzal, A., Rehman, A., & Dickert, F. (2007). Nanoparticles for detecting pollutants and degradation processes with mass-sensitive sensors. Sensors and Actuators B: Chemical, 127(1), 132–136.
Abstract: Compared with thin films, nanoparticle layers as coatings for QCM offer substantially increased interaction areas and sensitivities with favourable response times. Molybdenum disulphide (MoS2), e.g. has turned out to be a highly suitable material for interacting with thiols. The resulting materials are sufficiently soft according to Pearson to bind sulphur containing compounds reversibly. Depositing MoS2 nanoparticle submonolayers (particle size 200–300 nm) leads to an increase in sensor response by a factor of ten compared to a pure gold layer. Additionally, the nanoparticle layers show fully reversible sensor signals. Particle synthesis can also be combined with the molecular imprinting approach: by a precipitation technique, it is possible to generate molecularly imprinted TiO2 particles for engine oil degradation measurements. Compared with deposited thin layers, particles incorporate oxidised compounds from lubricants by a factor of two better.
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Шангина, Е. Л., Смирнов, К. В., Морозов, Д. В., Ковалюк, В. В., Гольцман, Г. Н., Веревкин, А. А., et al. (2010). Концентрационная зависимость полосы преобразования смесителей субмиллиметрового диапазона на основе наноструктур AlGaAs/GaAs. Изв. РАН Сер. Физ., 74(1), 110–112.
Abstract: Методом субмиллиметровой спектроскопии с высоким временным разрешением при Т = 4.2 К измерена концентрационная зависимость полосы преобразования гетеродинного детектирования гетероструктур AlGaAs/GaAs с двумерным электронным газом. С увеличением концентрации двумерных электронов ns = (1.6–6.6) · 1011см-2 ширина полосы преобразования f3dB уменьшается от 245 до 145 МГц. В исследованной области концентраций наблюдается зависимость f3dB , обусловленная рассеянием электронов на деформационном потенциале акустических фононов и пьезоэлектрическим рассеянием.
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Mitin, V., Antipov, A., Sergeev, A., Vagidov, N., Eason, D., & Strasser, G. (2011). Quantum Dot Infrared Photodetectors: Photoresponse Enhancement Due to Potential Barriers. Nanoscale res lett, 6(1), 6.
Abstract: Potential barriers around quantum dots (QDs) play a key role in kinetics of photoelectrons. These barriers are always created, when electrons from dopants outside QDs fill the dots. Potential barriers suppress the capture processes of photoelectrons and increase the photoresponse. To directly investigate the effect of potential barriers on photoelectron kinetics, we fabricated several QD structures with different positions of dopants and various levels of doping. The potential barriers as a function of doping and dopant positions have been determined using nextnano3 software. We experimentally investigated the photoresponse to IR radiation as a function of the radiation frequency and voltage bias. We also measured the dark current in these QD structures. Our investigations show that the photoresponse increases ~30 times as the height of potential barriers changes from 30 to 130 meV.
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Angeluts, A. A., Bezotosnyi, V. V., Cheshev, E. A., Goltsman, G. N., Finkel, M. I., Seliverstov, S. V., et al. (2014). Compact 1.64 THz source based on a dual-wavelength diode end-pumped Nd:YLF laser with a nearly semiconfocal cavity. Laser Phys. Lett., 11(1), 015004 (1 to 4).
Abstract: We describe a compact dual-wavelength (1.047 and 1.053 μm) diode end-pumped Q-switched Nd:YLE laser source which has a number of applications in demand. In order to achieve its dual-wavelength operation it is suggested for the first time to use essentially nonmonotonous dependences of the threshold pump powers at these wavelengths on the cavity length in the region of the cavity semiconfocal configuration under a radius of the pump beam smaller than the radius of the zero Gaussian mode. Here we demonstrate one of the most interesting applications for this laser: difference frequency generation in a GaSe crystal at a frequency of 1.64 THz. A superconducting hot-electron bolometer is used to detect the THz power generated and to measure its pulse characteristics.
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Shangina, E. L., Smirnov, K. V., Morozov, D. V., Kovalyuk, V. V., Gol’tsman, G. N., Verevkin, A. A., et al. (2010). Concentration dependence of the intermediate frequency bandwidth of submillimeter heterodyne AlGaAs/GaAs nanostructures. Bull. Russ. Acad. Sci. Phys., 74(1), 100–102.
Abstract: The concentration dependence of the intermediate frequency bandwidth of heterodyne AlGaAs/GaAs detectors with 2D electron gas is measured using submillimeter spectroscopy with high time resolution at T= 4.2 K. The intermediate frequency bandwidth f3dBfalls from 245 to 145 MHz with increasing concentration of 2D electrons n s = (1.6-6.6) × 10[su11] cm-2. The dependence f3dB ≈ n s – 0.04±is observed in the studied concentration range; this dependence is determined by electron scattering by the deformation potential of acoustic phonons and piezoelectric scattering.
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Nebosis, R. S., Heusinger, M. A., Schatz, W., Renk, K. F., Gol’tsman, G. N., Karasik, B. S., et al. (1993). Ultrafast photoresponse of a structured YBa2Cu3O7-δ thin film to ultrashort FIR laser pulses. IEEE Trans. Appl. Supercond., 3(1), 2160–2162.
Abstract: The authors have investigated the photoinduced voltage response of a current-carrying structured YBa2Cu3O7-δ thin film to ultrashort far-infrared (FIR) laser pulses in the frequency range from 0.7 THz to 7 THz. The detector has shown an almost constant sensitivity of 1 mV/W and a noise equivalent power of less than 5*10/sup -7/ W/ square root Hz. The temperature dependence of the decay time of the detector signal was studied for temperatures around the transition temperature of the film ( approximately 80 K). For a detector temperature where dR/dT had its maximum, the authors observed bolometric signals with decay times of about 2 ns, and for lower temperatures they observed nonbolometric signals with decay times of approximately 120 ps; the duration of the nonbolometric signals was limited by the time resolution of the electronic registration equipment.
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Semenov, A. D., Goghidze, I. G., Gol’tsman, G. N., Sergeev, A. V., Aksaev, E. E., & Gershenzon, E. M. (1993). Non-equilibrium quasiparticle response to radiation and bolometric effect in YBaCuO films. IEEE Trans. Appl. Supercond., 3(1), 2132–2135.
Abstract: The voltage photoresponse of structured current biased YBCO films on different substrates to 20-ps laser pulses of 0.63- mu m and 1.54- mu m wavelengths and to continuously modulated radiation of 2-mm wavelength is measured to temperatures around Tc. Fast picosecond decay of the response to pulsed radiation is followed by slow exponential relaxation with a nanosecond characteristic time depending on the substrate material and film dimensions. The slow component does not depend on wavelength and is attributed to the bolometric effect, while the magnitude of the fast component associated with nonequilibrium response rises with wavelength. More than an order-of-magnitude increase of the nonequilibrium response is seen from near-infrared to millimeter-wave range. This dependence plausibly reflects the low efficiency of multiplication of photoexcited electrons in YBaCuO compared to conventional superconductors.
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Kostiuk, T. (2003). Heterodyne spectroscopy in the thermal infrared region: a window on physics and chemistry. In University of Maryland Inn and Conference Center (Ed.), Proc. International Thermal Detectors Workshop (TDW'03), session 7 (Heterodyne detectors). 3501 University Boulevar East Adelphi, MD 20783.
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Heeres, R. W., Dorenbos, S. N., Koene, B., Solomon, G. S., Kouwenhoven, L. P., & Zwiller, V. (2010). On-Chip Single Plasmon Detection. Nano Lett., 10, 661–664.
Abstract: Surface plasmon polaritons (plasmons) have the potential to interface electronic and optical devices. They could prove extremely useful for integrated quantum information processing. Here we demonstrate on-chip electrical detection of single plasmons propagating along gold waveguides. The plasmons are excited using the single-photon emission of an optically emitting quantum dot. After propagating for several micrometers, the plasmons are coupled to a superconducting detector in the near-field. Correlation measurements prove that single plasmons are being detected.
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Gershenson, M. E., Gong, D., Sato, T., Karasik, B. S., & Sergeev, A. V. (2001). Millisecond electron-phonon relaxation in ultrathin disordered metal films at millikelvin temperatures. Appl. Phys. Lett., 79, 2049–2051.
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Siemsen, K. J., Bernard, J. E., Madej, A. A., & Marmet, L. (2001). Absolute frequency measurement of a CO2/OsO4 stabilized laser at 28.8 THz. Appl. Phys. B: Lasers and Optics, 72, 567–573.
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Zhou, Y. D., Becker, C. R., Ashokan, R., Selamet, Y., Chang, Y., Boreiko, R. T., et al. (2002). Progress in far-infrared detection technology. In Proc. SPIE (Vol. 4795, pp. 121–128). Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series.
Abstract: II-VI intrinsic very long wavelength infrared (VLWIR, λc~20 to 50 μm) materials, HgCdTe alloys as well as HgCdTe/CdTe superlattices, were grown by molecular beam epitaxy (MBE). The layers were characterized by means of X-ray diffraction, conventional Fourier transform infrared spectroscopy, Hall effect measurements and transmittance electron microscopy (TEM). Photoconductor devices were processed and their spectral response was also measured to demonstrate their applicability in the VLWIR region.
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(2003). InSb detectors technical data sheet.
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