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Author	Aberle, N.; Witte, U.
Title	*Deep-sea macrofauna exposed to a simulated sedimentation event in the abyssal NE Atlantic: in situ* pulse-chase experiments using ¹³C-labelled phytodetritus**			Type	Journal Article
Year	2003	Publication	Marine Ecology Progress Series	Abbreviated Journal	Mar Ecol Prog Ser
Volume	251	Issue		Pages	37-47
Keywords	Deep-sea; Pulse-chase experiment; δ¹³C; Benthic carbon remineralisation; Macrofauna; Atlantic Ocean, Porcupine Abyssal Plain
Abstract	Tracer experiments with ¹³C-labelled diatoms Thalassiosira rotula (Bacillariophycea, 98% ¹³C-labelled) were conducted at the Porcupine Abyssal Plain (PAP) in the NE Atlantic (BENGAL Station; 48<b0>50'N, 16<b0>30'W, 4850 m depth) during May/June 2000. In situ enrichment experiments were carried out using deep-sea benthic chamber landers: within the chambers a spring bloom was simulated and the fate of this food-pulse within the abyssal macrobenthic community was followed. In focus was the role of different macrofauna taxa and their vertical distribution within the sediment column in consuming and reworking the freshly deposited material. T. rotula is one of the most abundant pelagic diatoms in the NE Atlantic and therefore 0.2 g of freeze dried T. rotula, equivalent to 1 g algal C m^-2 yr^-1, was injected into each incubation chamber. Three different incubation times of 2.5, 8 and 23 d were chosen in order to follow the uptake of ¹³C-labelled phytodetritus by macrofauna. After only 2.5 d, 77% of all macrofauna organisms showed tracer uptake. After 23 d the highest degree of enrichment was measured and 95% of the individuals had taken up ¹³C from the introduced algal material. In addition to that a downward transport of organic matter was observed, even though the mixing was not very intense. The initial processing of carbon was dominated by polychaetes that made up a percentage of 52% of total macrofauna. In general macrofauna organisms that lived close to the sediment surface had higher access to the simulated food-pulse, confirming the hypothesis that individuals close to the sediment surface have the strongest impact on the decomposition of phytodetritus. In our study we observed only modest vertical entrainment of ¹³C tracers into the sediment. With regard to contradictory results from former ¹³C-enrichment experiments in bathyal regions, compared to results from our study site in the abyssal plain, we thus propose pronounced differences in feeding strategies between macrofauna communities from continental margins and abyssal plains.
Address	Aberle, Witte: Max Planck Institute for Marine Microbiology, Celsiusstr. 1, 28359 Bremen, Germany; Aberle: Present address: Max Planck Institute for Limnology, August-Thienemann-Str. 2, 24306 Pl<f6>n, Germany; Email: aberle@mpil-ploen.mpg.de
Corporate Author				Thesis
Publisher	Inter-Research	Place of Publication	Oldendorf/Luhe	Editor
Language	English	Summary Language	English	Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0171-8630	ISBN		Medium
Area	NE Atlantic	Expedition		Conference
Notes				Approved	no
Call Number	refbase @ user @ 706			Serial	4
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Author	Hirata, A.; Harada, M.; Nagatsuma, T.
Title	120-GHz wireless link using photonic techniques for generation, modulation, and emission of millimeter-wave signals			Type	Journal Article
Year	2003	Publication	J. of Lightwave Technology	Abbreviated Journal
Volume	21	Issue	10	Pages	2145-2153
Keywords	subterahartz terahertz THz communications
Abstract	We present a wireless link system that uses millimeter-wave (MMW) photonic techniques. The photonic transmitter in the wireless link consists of an optical 120-GHz MMW generator, an optical modulator, and a high-power photonic MMW emitter. A uni-traveling carrier photodiode (UTC-PD) was used as the photonic emitter in order to eliminate electronic MMW amplifiers. We evaluated the dependence of UTC-PD output power on its transit-time limited bandwidth and its CR-time constant limited bandwidth, and employed a UTC-PD with the highest output power for the photonic emitter. As for the MMW generation, we developed a 120-GHz optical MMW generator that generates a pulse train and one that generates a sinusoidal signal. The UTC-PD output power generated by a narrow pulse train was higher than that generated by sinusoidal signals under the same average optical power condition, which contributes to reducing the photocurrent of the photonic emitter. We have experimentally demonstrated that the photonic transmitter can transmit data at up to 3.0 Gb/s. The wireless link using the photonic transmitter can be applied to optical gigabit Ethernet signals.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	592
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Author	Vakhtomin, Y. B.; Finkel, M. I.; Antipov, S. V.; Smirnov, K. V.; Kaurova, N. S.; Drakinskii, V. N.; Voronov, B. M.; Gol’tsman, G. N.
Title	The gain bandwidth of mixers based on the electron heating effect in an ultrathin NbN film on a Si substrate with a buffer MgO layer			Type	Journal Article
Year	2003	Publication	J. of communications technol. & electronics	Abbreviated Journal	J. of communications technol. & electronics
Volume	48	Issue	6	Pages	671-675
Keywords	NbN HEB mixers
Abstract	Measurements of the intermediate frequency band 900 GHz of mixers based on the electron heating effect (EHE) in 2-nm- and 3.5-nm-thick superconducting NbN films sputtered on MgO and Si substrates with buffer MgO layers are presented. A 2-nm-thick superconducting NbN film with a critical temperature of 9.2 K has been obtained for the first time using a buffer MgO layer.
Address
Corporate Author				Thesis
Publisher	MAIK Nauka/Interperiodica, Birmingham, AL	Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1064-2269	ISBN		Medium
Area		Expedition		Conference
Notes	https://elibrary.ru/item.asp?id=17302119 (Полоса преобразования смесителей на эффекте разогрева электронов в ультратонких пленках NbN на подложках из Si с подслоем MgO)			Approved	no
Call Number	Vakhtomin2003			Serial	1522
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Author	Sobolewski, R.; Verevkin, A.; Gol'tsman, G.N.; Lipatov, A.; Wilsher, K.
Title	Ultrafast superconducting single-photon optical detectors and their applications			Type	Journal Article
Year	2003	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal
Volume	13	Issue	2	Pages	1151-1157
Keywords	NbN SSPD, SNSPD
Abstract	We present a new class of ultrafast single-photon detectors for counting both visible and infrared photons. The detection mechanism is based on photon-induced hotspot formation, which forces the supercurrent redistribution and leads to the appearance of a transient resistive barrier across an ultrathin, submicrometer-width, superconducting stripe. The devices were fabricated from 3.5-nm- and 10-nm-thick NbN films, patterned into <200-nm-wide stripes in the 4 /spl times/ 4-/spl mu/m/sup 2/ or 10 /spl times/ 10-/spl mu/m/sup 2/ meander-type geometry, and operated at 4.2 K, well below the NbN critical temperature (T/sub c/=10-11 K). Continuous-wave and pulsed-laser optical sources in the 400-nm-to 3500-nm-wavelength range were used to determine the detector performance in the photon-counting mode. Experimental quantum efficiency was found to exponentially depend on the photon wavelength, and for our best, 3.5-nm-thick, 100-/spl mu/m/sup 2/-area devices varied from >10% for 405-nm radiation to 3.5% for 1550-nm photons. The detector response time and jitter were /spl sim/100 ps and 35 ps, respectively, and were acquisition system limited. The dark counts were below 0.01 per second at optimal biasing. In terms of the counting rate, jitter, and dark counts, the NbN single-photon detectors significantly outperform their semiconductor counterparts. Already-identified applications for our devices range from noncontact testing of semiconductor CMOS VLSI circuits to free-space quantum cryptography and communications.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1051-8223	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	509
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Author	Meledin, D.; Tong, C. Y.-E.; Blundell, R.; Kaurova, N.; Smirnov, K.; Voronov, B.; Gol'tsman, G.
Title	Study of the IF bandwidth of NbN HEB mixers based on crystalline quartz substrate with an MgO buffer layer			Type	Journal Article
Year	2003	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal	IEEE Trans. Appl. Supercond.
Volume	13	Issue	2	Pages	164-167
Keywords	NbN HEB mixer
Abstract	In this paper, we present the results of IF bandwidth measurements on 3-4 nm thick NbN hot electron bolometer waveguide mixers, which have been fabricated on a 200-nm thick MgO buffer layer deposited on a crystalline quartz substrate. The 3-dB IF bandwidth, measured at an LO frequency of 0.81 THz, is 3.7 GHz at the optimal bias point for low noise receiver operation. We have also made measurements of the IF dynamic impedance, which allow us to evaluate the intrinsic electron temperature relaxation time and self-heating parameters at different bias conditions.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	341
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Author	Semenov, A. D.; Hübers, Heinz-Wilhelm; Richter, H.; Birk, M.; Krocka, M.; Mair, U.; Vachtomin, Yu. B.; Finkel, M. I.; Antipov, S. V.; Voronov, B. M.; Smirnov, K. V.; Kaurova, N. S.; Drakinski, V. N.; Gol'tsman, G. N.
Title	Superconducting hot-electron bolometer mixer for terahertz heterodyne receivers			Type	Journal Article
Year	2003	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal
Volume	13	Issue	2	Pages	168-171
Keywords	NbN HEB mixers
Abstract	We present recent results showing the development of superconducting NbN hot-electron bolometer mixer for German receiver for astronomy at terahertz frequencies and terahertz limb sounder. The mixer is incorporated into a planar feed antenna, which has either logarithmic spiral or double-slot configuration, and backed on a silicon lens. The hybrid antenna had almost frequency independent and symmetric radiation pattern slightly broader than expected for a diffraction limited antenna. At 2.5 THz the best 2200 K double side-band receiver noise temperature was achieved across a 1 GHz intermediate frequency bandwidth centred at 1.5 GHz. For this operation regime, a receiver conversion efficiency of -17 dB was directly measured and the loss budget was evaluated. The mixer response was linear at load temperatures smaller than 400 K. Implementation of the MgO buffer layer on Si resulted in an increased 5.2 GHz gain bandwidth. The receiver was tested in the laboratory environment by measuring a methanol emission line at 2.5 THz.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	343
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Author	Zhang, Jin; Slysz, W.; Verevkin, A.; Okunev, O.; Chulkova, G.; Korneev, A.; Lipatov, A.; Gol'tsman, G. N.; Sobolewski, R.
Title	Response time characterization of NbN superconducting single-photon detectors			Type	Journal Article
Year	2003	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal
Volume	13	Issue	2	Pages	180-183
Keywords	SSPD jitter, SNSPD jitter
Abstract	We report our time-resolved measurements of NbN-based superconducting single-photon detectors. The structures are meander-type, 10-nm thick, and 200-nm wide stripes and were operated at 4.2 K. We have shown that the NbN devices can count single-photon pulses with below 100-ps time resolution. The response signal pulse width was about 150 ps, and the system jitter was measured to be 35 ps.
Address
Corporate Author				Thesis
Publisher	IEEE	Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1058
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Author	Gol’tsman, G. N.; Smirnov, K.; Kouminov, P.; Voronov, B.; Kaurova, N.; Drakinsky, V.; Zhang, J.; Verevkin, A.; Sobolewski, R.
Title	Fabrication of nanostructured superconducting single-photon detectors			Type	Journal Article
Year	2003	Publication	IEEE Trans. Appl. Supercond.	Abbreviated Journal	IEEE Trans. Appl. Supercond.
Volume	13	Issue	2	Pages	192-195
Keywords	NbN SSPD, SNSPD
Abstract	Fabrication of NbN superconducting single-photon detectors, based on the hotspot effect is presented. The hotspot formation arises in an ultrathin and submicrometer-width superconductor stripe and, together with the supercurrent redistribution, leads to the resistive detector response upon absorption of a photon. The detector has a meander structure to maximally increase its active area and reach the highest detection efficiency. Main processing steps, leading to efficient devices, sensitive in 0.4-5 /spl mu/m wavelength range, are presented. The impact of various processing steps on the performance and operational parameters of our detectors is discussed.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1558-2515	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1515
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Author	Tong, C.-Y. E.; Meledin, D.; Loudkov, D.; Blundell, R.; Erickson, N.; Kawamura, J.; Mehdi, I.; Gol’tsman, G.
Title	A 1.5 THz Hot-Electron Bolometer mixer operated by a planar diode based local oscillator			Type	Conference Article
Year	2003	Publication	IEEE MTT-S Int. Microwave Symp. Digest	Abbreviated Journal	IEEE MTT-S Int. Microwave Symp. Digest
Volume	2	Issue		Pages	751-754
Keywords	waveguide NbN HEB mixers
Abstract	We have developed a 1.5 THz superconducting NbN Hot-Electron Bolometer mixer. It is operated by an all-solid-state Local Oscillator comprising of a cascade of 4 planar doublers following an MMIC based W-band power amplifier. The threshold available pump power is estimated to be 1 /spl mu/W.
Address	Philadelphia, PA, USA
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1516
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Author	Meledin, D.; Tong, C.-Y. E.; Blundell, R.; Goltsman, G.
Title	Measurement of intermediate frequency bandwidth of hot electron bolometer mixers at terahertz frequency range			Type	Journal Article
Year	2003	Publication	IEEE Microw. Wireless Compon. Lett.	Abbreviated Journal	IEEE Microw. Wireless Compon. Lett.
Volume	13	Issue	11	Pages	493-495
Keywords	waveguide NbN HEB mixers
Abstract	We have developed a new experimental setup for measuring the IF bandwidth of superconducting hot electron bolometer mixers. In our measurement system we use a chopped hot filament as a broadband signal source, and can perform a high-speed IF scan with no loss of accuracy when compared to coherent methods. Using this technique we have measured the 3 dB IF bandwidth of hot electron bolometer mixers, designed for THz frequency operation, and made from 3-4 nm thick NbN film deposited on an MgO buffer layer over crystalline quartz.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1531-1309	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1509
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Author	Tong, C.-Y.E.; Meledin, D.V.; Marrone, D.P.; Paine, S.N.; Gibson, H.; Blundell, R.
Title	Near field vector beam measurements at 1 THz			Type	Journal Article
Year	2003	Publication	IEEE Microw. Compon. Lett.	Abbreviated Journal
Volume	13	Issue	6	Pages	235-237
Keywords	HEB, mixer, waveguide, LO power, local oscillator power, saturation effect, dynamic range
Abstract	We have performed near-field vector beam measurements at 1.03 THz to characterize and align the receiver optics of a superconducting receiver. The signal source is a harmonic generator mounted on an X-Y translation stage. We model the measured two-dimensional complex beam pattern by a fundamental Gaussian mode, from which we derive the position of the beam center, the beam radius and the direction of propagation. By performing scans in the planes separated by 400 mm, we have confirmed that our beam pattern measurements are highly reliable.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1531-1309	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number	RPLAB @ lobanovyury @			Serial	574
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Author	Semenov, A.; Engel, A.; Il'in, K.; Gol'tsman, G.; Siegel, M.; Hübers, H.-W.
Title	Ultimate performance of a superconducting quantum detector			Type	Journal Article
Year	2003	Publication	Eur. Phys. J. Appl. Phys.	Abbreviated Journal	Eur. Phys. J. Appl. Phys.
Volume	21	Issue	3	Pages	171-178
Keywords	NbN SSPD, SNSPD
Abstract	We analyze the ultimate performance of a superconducting quantum detector in order to meet requirements for applications in near-infrared astronomy and X-ray spectroscopy. The detector exploits a combined detection mechanism, in which avalanche quasiparticle multiplication and the supercurrent jointly produce a voltage response to a single absorbed photon via successive formation of a photon-induced and a current-induced normal hotspot in a narrow superconducting strip. The response time of the detector should increase with the photon energy providing energy resolution. Depending on the superconducting material and operation conditions, the cut-off wavelength for the single-photon detection regime varies from infrared waves to visible light. We simulated the performance of the background-limited infrared direct detector and X-ray photon counter utilizing the above mechanism. Low dark count rate and intrinsic low-frequency cut-off allow for realizing a background limited noise equivalent power of 10−20 W Hz−1/2 for a far-infrared direct detector exposed to 4-K background radiation. At low temperatures, the intrinsic response time of the counter is rather determined by diffusion of nonequilibrium electrons than by the rate of energy transfer to phonons. Therefore, thermal fluctuations do not hamper energy resolution of the X-ray photon counter that should be better than 10−3 for 6-keV photons. Comparison of new data obtained with a Nb based detector and previously reported results on NbN quantum detectors support our estimates of ultimate detector performance.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1286-0042	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	534
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Author	Zhang, J.; Boiadjieva, N.; Chulkova, G.; Deslandes, H.; Gol'tsman, G. N.; Korneev, A.; Kouminov, P.; Leibowitz, M.; Lo, W.; Malinsky, R.; Okunev, O.; Pearlman, A.; Slysz, W.; Smirnov, K.; Tsao, C.; Verevkin, A.; Voronov, B.; Wilsher, K.; Sobolewski, R.
Title	Noninvasive CMOS circuit testing with NbN superconducting single-photon detectors			Type	Journal Article
Year	2003	Publication	Electron. Lett.	Abbreviated Journal	Electron. Lett.
Volume	39	Issue	14	Pages	1086-1088
Keywords	NbN SSPD, SNSPD, applications
Abstract	The 3.5 nm thick-film, meander-structured NbN superconducting single-photon detectors have been implemented in the CMOS circuit-testing system based on the detection of near-infrared photon emission from switching transistors and have significantly improved the performance of the system. Photon emissions from both p- and n-MOS transistors have been observed.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0013-5194	ISBN		Medium
Area		Expedition		Conference
Notes				Approved	no
Call Number				Serial	1512
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Author	Verevkin, A.; Slysz, W.; Pearlman, A.; Zhang, J.; Sobolewski, R.; Okunev, O.; Korneev, A.; Kouminov, P.; Smirnov, K.; Chulkova, G.; Gol’tsman, G. N.; Currie, M.
Title	Real-time GHz-rate counting of infrared photons using nanostructured NbN superconducting detectors			Type	Conference Article
Year	2003	Publication	CLEO/QELS	Abbreviated Journal	CLEO/QELS
Volume		Issue		Pages	CThM8
Keywords	NbN SSPD; SNSPD; Infrared; Quantum detectors; Detectors; Photon counting; Quantum communications; Quantum cryptography; Single photon detectors; Superconductors
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.
Address
Corporate Author				Thesis
Publisher	Optical Society of America	Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference
Notes				Approved	no
Call Number				Serial	1517
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Author	Zhang, J.; Pearlman, A.; Slysz, W.; Verevkin, A.; Sobolewski, R.; Okunev, O.; Korneev, A.; Kouminov, P.; Smirnov, K.; Chulkova, G.; Gol’tsman, G. N.; Lo, W.; Wilsher, K.
Title	Infrared picosecond superconducting single-photon detectors for CMOS circuit testing			Type	Conference Article
Year	2003	Publication	CLEO/QELS	Abbreviated Journal	CLEO/QELS
Volume		Issue		Pages	Cmv4
Keywords	NbN SSPD; SNSPD; Infrared; Quantum detectors; Electron beam lithography; Infrared detectors; Infrared radiation; Quantum efficiency; Single photon detectors; Superconductors
Abstract	Novel, NbN superconducting single-photon detectors have been developed for ultrafast, high quantum efficiency detection of single quanta of infrared radiation. Our devices have been successfully implemented in a commercial VLSI CMOS circuit testing system.
Address
Corporate Author				Thesis
Publisher	Optical Society of America	Place of Publication		Editor
Language		Summary Language		Original Title
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN		ISBN		Medium
Area		Expedition		Conference	Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference
Notes				Approved	no
Call Number				Serial	1518
Permanent link to this record