15 Fakultätsübergreifend / Sonstige Einrichtung

Permanent URI for this collectionhttps://elib.uni-stuttgart.de/handle/11682/16

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Open Access
Ein 1λ5, 3λ5, 5λ3-Triphosphabenzol-Derivat
(1986) Fluck, Ekkehard; Becker, Gerd; Neumüller, Bernhard; Knebl, Robert; Heckmann, Gernot; Riffel, Heinz
Die erste Ringverbindung mit (PC)3-Gerüst, die Titelverbindung 3, wurde wie unten skizziert hergestellt. Die 13C-NMR-Daten deuten auf einen hohen Ylid-Charakter der Gruppierung C4-P5-C6 hin.
Open Access
A 1λ5,3λ5,5λ3-triphosphabenzene derivative
(1986) Fluck, Ekkehard; Becker, Gerd; Neumüller, Bernhard; Knebl, Robert; Heckmann, Gernot; Riffel, Heinz
The first ring compound containing the (P=C)3 skeleton, the title compound 3, was prepared as shown below. 13C-NMR data indicate a highly ylidic character of the C4-P5-C6 grouping.
Open Access
1,3,5-Tris(dimethylamino)benzol mit Iod und 1,3,5-Tricyanobenzol : eine ungewöhnliche Dimerisierung und ein "normaler" Donor/Akzeptor-Komplex
(1988) Keller, Heimo J.; Niebl, Roland; Renner, Gerd; Ruhr, Dorothea von der; Schweitzer, Dieter
Wir sind auf der Suche nach "organischen" Ferromagneten. Als Zielsubstanz haben wir kristallisierte Radikal-Ionen mit bahnentarteten Grundzuständen ausgewählt. Molekulare Festkörper aus planaren organischen Radikalionen zeigen ein breites Spektrum teilweise recht interessanter physikalischer Eigenschaften, die durch kollektives Elektronenverhalten zu erklären sind. In den letzten Jahren wurde vor allem das elektrische Verhalten dieser Substanzen untersucht. Dies führte zur Entdeckung einer Vielzahl "organischer Metalle", von denen einige bei tiefer Temperatur auch supraleitend werden.
Open Access
1,8-dipyrenylnaphthalenes : syntheses, molecular structure, and spectroscopic properties
(1984) Wahl, Peter; Krieger, Claus; Schweitzer, Dieter; Staab, Heinz A.
Syntheses of the 1,8-dipyrenylnaphthalenes 1-3 are reported. The stereoisomers 1 and 2 were separated; their structural assignment is based on 1H NMR, on the optical activity of 2, and on X-ray structure analyses of 1 and 2. Kinetic parameters for the isomerisation 2 = 1 were determined by optical rotation measurements. - Emission spectra of 1 - 3 are discussed in comparison to monopyrenyl compounds 4 and 8. For 1 and 3 typical 'excimer-like' fluorescence is observed. The difference between 1 and 2 clearly demonstrates the dependence of excimer interactions between the pyrene units on the mutual orientation of the π-systems involved. - On the basis of X-ray analyses the molecular structures of 1- 3 are discussed with emphasis on π···π-interactions between the pyrene units.
Open Access
1.3 μm monolithic integrated optoelectronic receiver using InGaAs MSM photodiode and AlGaAs/GaAs HEMTs grown on GaAs
(1994) Hurm, Volker; Benz, Willi; Berroth, Manfred; Fink, Thomas; Fritzsche, Daniel; Haupt, Michael; Hofmann, Peter; Köhler, Klaus; Ludwig, Manfred; Mause, Klaus; Raynor, Brian; Rosenzweig, Josef
The first 1.3 μm monolithic integrated optoelectronic receiver using an InGaAs MSM photodiode and AlGaAs/GaAs HEMTs grown on a GaAs substrate has been fabricated. At each differential output the transimpedance is 26.8 kΩ. The bandwidth of 430 MHz implies suitability for transmission rates up to 622 Mbit/s.
Open Access
10 Gb/s monolithic integrated MSM-photodiode AlGaAs/GaAs-HEMT optoelectronic receiver
(1991) Hurm, Volker; Rosenzweig, Josef; Ludwig, Manfred; Benz, Willi; Osorio, Ricardo; Berroth, Manfred; Hülsmann, Axel; Kaufel, Gudrun; Köhler, Klaus; Raynor, Brian; Schneider, Joachim
A photoreceiver based on a metal-semiconductor-metal (MSM) photodiode and AlGaAs/GaAs HEMTs is presented. The photoreceiver was fabricated using a 0.5-μm recessed-gate process for double delta-doped quantum-well HEMTs. The following mean values for the enhancement and depletion HEMT parameters, respectively, have been obtained: threshold voltages of 0.1 and -0.5 V, transconductances of 500 and 390 mS/mm, source resistances of 0.7 and 0.6 Ω-mm, and transit frequencies of 35 and 30 GHz. This process includes photodiodes. A deep wet etch was used to deposit the photodiodes on an undoped GaAs buffer layer.
Open Access
10 Gbit/s monolithic integrated Msm-photodiode AlGaAs/GaAs-HEMT optoelectronic receiver
(1991) Hurm, Volker; Rosenzweig, Josef; Ludwig, Manfred; Benz, Willi; Osorio, Ricardo; Berroth, Manfred; Hülsmann, Axel; Kaufel, Gudrun; Köhler, Klaus; Raynor, Brian; Schneider, Joachim
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Open Access
10 Gbit/s monolithic integrated optoelectronic receiver using an MSM photodiode and AlGaAs/GaAs HEMTs
(1991) Hurm, Volker; Rosenzweig, Josef; Ludwig, Manfred; Axmann, Albert; Benz, Willi; Berroth, Manfred; Osorio, Ricardo; Hülsmann, Axel; Kaufel, Gudrun; Köhler, Klaus; Raynor, Brian; Schneider, Joachim
A 10 Gbit/s monolithic integrated optoelectronic receiver has been fabricated with a metal-semiconductor-metal (MSM) photodiode and enhancement/depletion 0.5 μm recessed-gate AlGaAs/GaAs HEMTs. A -3 dB bandwidth of 11.3 GHz has been achieved.
Open Access
10-20 Gbit/s GaAs/AlGaAs HEMT ICs for high speed data links
(1992) Berroth, Manfred; Hurm, Volker; Lang, Manfred; Ludwig, Manfred; Nowotny, Ulrich; Wang, Zhigong; Wennekers, Peter; Hülsmann, Axel; Kaufel, Gudrun; Köhler, Klaus; Raynor, Brian; Schneider, Joachim
A set of ICs has been developed for high-speed data links at data rates above 10 Gbit/s. A recessed gate process for double pulse doped quantum well transistors has been used with e-beam written 0.3- μm gates. A 4 bit multiplexer and a laser diode driver for the transmitter as well as a transimpedance amplifier, bit synchronizer, and 4 bit demultiplexer for the receiver have been successfully operated with data rates up to 20 Gbit/s.
Open Access
11.6 Gbps 1:4 demultiplexer using double pulse doped quantum well GaAs/AlGaAs transistors
(1991) Lang, Manfred; Nowotny, Ulrich; Berroth, Manfred
An ultrahigh speed 4 bit demultiplexer circuit has been developed and fabricated using a recessed gate process for enhancement and depletion transistors with 0.3 mu m gate length. First results show a data rate of 11.6 Gbit/s and a power consumption of 165 mW at 0.85 V supply voltage, including four 50 Omega buffers.
Open Access
13C nuclear magnetic relaxation studies at 62 MHz
(1971) Jaeckle, H.; Haeberlen, Ulrich; Schweitzer, Dieter
An apparatus suitable to measure 13C relaxation times T1 and T2 in liquids at 62 MHz is described. The required field of 58 kG is generated by a superconducting magnet. Results of T1 measurements on a variety of liquids, including benzene, derivatives of benzene, saturated rings, CS2, and others are reported. They are discussed in terms of dipole-dipole interactions, spin-rotation interactions and anisotropic chemical shifts, the latter of which turn out to play only a minor role. Intramolecular dipole-dipole interactions are found to provide by far the most important spin-lattice relaxation mechanism, whenever protons are bound directly to the carbons under investigation, even when the samples contain dissolved oxygen.
Open Access
14 GHz bandwidth MSM photodiode AlGaAs/GaAs HEMT monolithic integrated optoelectronic receiver
(1993) Hurm, Volker; Ludwig, Manfred; Rosenzweig, Josef; Benz, Willi; Berroth, Manfred; Bosch, Roland; Bronner, Wolfgang; Hülsmann, Axel; Köhler, Klaus; Raynor, Brian; Schneider, Joachim
A monolithic optoelectronic receiver consisting of an MSM photodiode and a two-stage amplifer has been fabricated using an enhancement/depletion 0.3 μm recessed-gate AlGaAs/GaAs HEMT process. The band-width of 14.3 GHz implies suitability for transmission rates of up 20 Gbit/s. The transimpendance is 670 Ω (into 50 Ω) and the projected sensitivity is 16.4 dBm (BER = 10 -9).
Open Access
15 Gbit/s integrated laser diode driver using 0.3 μm gate length quantum well transistors
(1992) Wang, Zhigong; Berroth, Manfred; Nowotny, Ulrich; Gotzeina, Werner; Hofmann, Peter; Hülsmann, Axel; Kaufel, Gudrun; Köhler, Klaus; Raynor, Brian; Schneider, Joachim
An integrated laser diode driver was realised using enhancement/depletion 0.3 μm recessed-gate AlGaAs/GaAs quantum well transistors. Fully-open eye diagrams were observed at bit rates up to 10 Gbit/s with 50 Ω loads. The maximum DC and modulation current were 25 and 45 mA, respectively. The power consumption is less than 450 mW.
Open Access
15N and 13C spin lattice relaxation in neat liquids at high magnetic fields
(1975) Schweitzer, Dieter; Spiess, Hans Wolfgang
General features of 15N spin lattice relaxation in nitrobenzene, pyridine and triethanolamine are discussed and compared with l3C relaxation mechanisms.
Open Access
16 x 16 bit parallel multiplier based on 6 K gate array with 0.3 μm AlGaAs/GaAs quantum well transistors
(1992) Thiede, Andreas; Berroth, Manfred; Hurm, Volker; Nowotny, Ulrich; Seibel, Jörg; Gotzeina, W.; Sedler, Martin; Raynor, Brian; Köhler, Klaus; Hofmann, Peter; Hülsmann, Axel; Kaufel, Gudrun; Schneider, Joachim
The design and performance of a 16x16 bit parallel multiplier based on a 6 K gate array will be presented. This LSI semicustom IC demonstrates the high potential of the authors' AlGaAs/GaAs quantum well FETs with a gate length of 0.3 μm. The best multiplication time measured was 7.2 ns.
Open Access
18 Gbit/s monolithically integrated 2:1 multiplexer and laser driving using 0.3 μm gate length quantum well HEMTs
(1992) Wang, Zhigong; Nowotny, Ulrich; Berroth, Manfred; Bronner, Wolfgang; Hofmann, Peter; Hülsmann, Axel; Köhler, Klaus; Raynor, Brian; Schneider, Joachim
A monolithically integrated 2:1 multiplexer and laser diode driver was developed, using AlGaAs quantum well HEMTs of 0.3 μm gate length. The DC and modulation current is 25 and 45 mA, respectively. Open eye diagrams were measured at bit rates up to 18 Gbit/s with pseudorandom data streams.
Open Access
An 18-34-GHz dynamic frequency divider based on 0.2-μm AlGaAs/GaAs/AlGaAs quantum-well transistors
(1993) Thiede, Andreas; Berroth, Manfred; Nowotny, Ulrich; Seibel, Jörg; Bosch, Roland; Köhler, Klaus; Raynor, Brian; Schneider, Joachim
The design and performance of a dynamic frequency divider was presented. This digital IC demonstrates the ability of the authors' AlGaAs/GaAs/AlGaAs quantum-well FETs with gate lengths of 0.2 μm. Stable operation was achieved in the frequency range from 18 GHz up to 34 GHz with a power consumption of 250 mW. To the authors' knowledge, this is the best result ever reported for HEMT circuits, and is similar to the frequency limit achieved by use of AlGaAs/GaAs HBTs.
Open Access
19 GHz monolithic integrated clock recovery using PLL and 0.3 μm gate-length quantum-well HEMTs
(1994) Wang, Zhigong; Berroth, Manfred; Seibel, Jörg; Hofmann, Peter; Hülsmann, Axel; Köhler, Klaus; Raynor, Brian; Schneider, Joachim
ICs for optical data links have been developed for bit rates between 10 and 200 Gb/s. The only exception was the clock recovery (CR) IC at these high bit rates. In fact, the IC realization of CR is generally accepted as the weak point of high-speed system integration. While the bit rates of some ICs reach up to 40 Gb/s, monolithic ICs for a full CR function are limited to 2.5 Gb/s. The monolithic IC described here, for CR with a PLL including a full-balanced VCO, is based on the IC reported by Wang et. al. (1993). Clock frequencies up to 19 GHz are recovered with the IC reported here.
Open Access
(2,2,8,8-tetramethyl-5-oxa-4,6-diphospha-3,6-nonadiene)tetrakis[dicarbonyl(methylcyclopentadienyl)manganese], the first complexed bis(phosphavinyl) ether
(1987) Ziegler, Manfred L.; Balles, Rainer; Nuber, Bernd; Becker, Gerd; Schmidt, Helmut; Kanellakopulos, Basil; Powietzka, Bernhard
The title compound 1 is the complex of a novel ligand. It is formed from [(CH3C5H4)Mn(CO)2·thf] and (CH3)3C-C=P, presumably with uptake of H2O. The bis(phosphavinyl) ether in 1 functions as an 8-electron donor toward the four (CH3C5H4)Mn(CO)2 units (abbreviated here as Mn).
Open Access
2,2-Dimethylpropylidinphosphan, eine stabile Verbindung mit einem Phosphoratom der Koordinationszahl 1 (Acyl- und Alkylidenphosphane ; 15)
(1981) Becker, Gerd; Gresser, Gudrun; Uhl, Werner
In the presence of small amounts of solid sodium hydroxide, (2,2-dimethyl-1-(trimethyl-siloxy)propylidene]-trimethylsilylphosphine reacts at + 20° C to give hexamethydisiloxane and 2,2-dimethylpropylidynephosphine (2). In contrast to similar alkylidynephosphines this compound is stabIe at room temperature. The IR and mass spectrum are discussed, and 1 H, 13 C and 31 PNMR spectral data are given.