Band structure of ZnO from resonant x-ray emission spectroscopy (2008)
Preston, A. R. H., Ruck, B. J., Piper, L. F. J., DeMasi, A., Smith, K. E., Schleife, A., ...
Soft x-ray emission and absorption spectroscopy of the O K-edge are employed to investigate the electronic structure of wurtzite ZnO(0001). A quasiparticle band structure calculated within the GW...
Fuchs, F., Rödl, C., Schleife, A., Bechstedt, F.
Excitonic effects in optical spectra and electron-hole pair excitations are described by solutions of the Bethe-Salpeter equation (BSE) that accounts for the Coulomb interaction of excited...
OFDEX-optial stand-off detection of explosives and improvised explosive devices (2008)
Bronner, W., Fuchs, F., Köhler, K., Wagner, J., Wild, C., Bunte, G., ...
Current- and temperature-induced beam steering in 7.8-µm emitting quantum-cascade lasers (2008)
Hinkov. B., Fuchs, F., Bronner, W., Köhler, K., Wagner, J.
We report large current- and temperature-induced beam-steering effects, observed in the far-field distribution of InP-based quantum-cascade lasers emitting around 7.8-µm wavelength operated in...
Yang, Q.K., Manz, C., Bronner, W., Lehmann, N., Fuchs, F., Köhler, K., ...
High peak-power operation of quaternary-barrier GaInAs/AlGaAsSb quantum-cascade lasers emitting at lambda about 3.6-3.8 µm is reported. With as-cleaved facets, the lasers (18 µm x 2.7 mm) emit a...
Remote sensing of explosives using mid-infrared quantum cascade lasers (2007)
Fuchs, F., Wild, C., Rahmouni, Y., Bronner, W., Raynor, B., Köhler, K., ...
The spectroscopic detection of complex molecules, such as explosives, requires a much broader spectral tuning range of the employed laser compared to the well-established tunable diode laser...
GW band structure of InAs and GaAs in the wurtzite phase (2006)
Zanolli, Z., Fuchs, F., Furthmueller, J., Von Barth, U., Bechstedt, F.
We report the first quasiparticle calculations of the newly observed wurtzite polymorph of InAs and GaAs. The calculations are performed in the GW approximation using plane waves and...
Schleife, A., Fuchs, F., Furthmüller, J., Bechstedt, F.
An ab initio pseudopotential method based on density functional theory, generalized gradient corrections to exchange and correlation, and projector-augmented waves is used to investigate structural,...
Quasiparticle band structure based on a generalized Kohn-Sham scheme (2006)
Fuchs, F., Furthmüller, J., Bechstedt, F., Shishkin, M., Kresse, G.
We present a comparative full-potential study of generalized Kohn-Sham schemes (gKS) with explicit focus on their suitability as starting point for the solution of the quasiparticle equation. We...
Fuchs, F., Kirn, B., Mann, C., Yang, Q.K., Bronner, W., Raynor, B., ...
We present a study of the spectral characteristics of Fabry-Perot quantum cascade lasers in pulsed mode operation applying a time resolution of 3 ns in combination with a high spectral resolution of...
Nonequilibrium radiation of long-wavelength InAs/GaSb superlattice photodiodes (2006)
Hoffmann, D., Hood, A., Fuchs, F., Razeghi, M.
The emission behavior of binary-binary type-II InAs/GaSb superlattice photodiodes has been studied in the spectral range between 8 and 13 µm. With a radiometric calibration of the experimental setup...
Negative luminescence of InAs/GaSb superlattice photodiodes (2006)
Fuchs, F., Hoffmann, D., Gin, A., Hood, A., Wei, Y., Razeghi, M.
The emission behaviour of InAs/GaSb superlattice photodiodes has been studied in the spectral range between 8 µm and 13 µm. With a radiometric calibration of the experimental set-up the internal...
Electroluminescence of InAs-GaSb heterodiodes (2006)
Hoffmann, D., Hood, A., Michel, E., Fuchs, F., Razeghi, M.
The electroluminescence of a Type II InAs-GaSb superlattice heterodiode has been studied as a function of injection current and temperature in the spectral range between 3 and 13 µm. The heterodiode...
Capacitance-voltage investigation of high-purity InAs/GaSb superlattice photodiodes (2006)
Hood, A., Hoffmann, D., Wei, Y., Fuchs, F., Razeghi, M.
The residual carrier backgrounds of binary type-II InAs/GaSb superlattice photodiodes with cutoff wavelengths around 5 µm have been studied in the temperature range between 20 and 200 K. By applying...
InAs/GaSb superlattice focal plane arrays for high-resolution thermal imaging (2006)
Rehm, R., Walther, M., Schmitz, J., Fleißner, J., Fuchs, F., Ziegler, J., ...
The first fully operational mid-IR (3-5 µm) 256×256 IR-FPA camera system based on a type-II InAs/GaSb short-period superlattice showing an excellent noise equivalent temperature difference below 10...
Mann, C., Yang, Q.K., Fuchs, F., Bronner, W., Köhler, K., Wagner, J.
The influence of injector doping concentration N(inj) on the performance of InP-based quantum-cascade (QC) lasers is investigated for devices emitting around 9.2-µm wavelength and injector doping...
Rehm, R., Walther, M., Fuchs, F., Schmitz, J., Fleißner, J.
An approach for the passivation of photodiodes based on compounds of the InAs/ GaSb/ AlSb materials family is presented. The passivation is realized by the overgrowth of patterned mesa devices with a...
Yang, Q.K., Mann, C., Fuchs, F., Köhler, K., Bronner, W.
Conventional strain-compensated quantum cascade (QC) lasers are fabricated with both tensile. strained AlInAs and compressively strained GaInAs layers. We show that strain compensation can also be...
Third generation focal plane array IR detection modules and applications (2005)
Cabanski, W., Münzberg, M., Rode, W., Wendler, J., Ziegler, J., Fleißner, J., ...
The 3rd generation of infrared (IR) detection modules is expected to provide advanced features like higher resolution 1024x1024 or 1280x720 pixels and/or new functions like multicolor or multi band...
InAs/(GaIn)Sb short-period superlattices for focal plane arrays (2005)
Rehm, R., Walther, M., Schmitz, J., Fleißner, J., Fuchs, F., Cabanski, W., ...
An infrared camera based on a 256x256 focal plane array for the Mid-IR spectral range (3-5 mu m) has been realized for the first time with InAs/GaSb short-period superlattices. The detector shows a...
Hoffmann, D., Gin, A., Wei, Y., Hood, A., Fuchs, F., Razeghi, M.
The quantum efficiency of negative and positive luminescence in binary type-II InAs-GaSb superlattice photodiodes has been investigated in the midinfrared spectral range around the 5-µm wavelength....
Physics and applications of InAs/(GaIn)Sb-based short period superlattices (2005)
Fuchs, F., Rehm, R., Schmitz, J., Fleißner, J., Walther, M.
The physical properties of the InAs/GaInSb SL system are described with emphasis on the application for infrared detection. Examples for material optimization using optical methods, such as...
Negative luminescence of long-wavelength InAs/GaSb superlattice photodiodes (2005)
Hoffmann, D., Hood, A., Wei, Y., Gin, A., Fuchs, F., Razeghi, M.
The electrically pumped emission behavior of binary type-II InAs/GaSb superlattice photodiodes has been studied in the spectral range between 8 µm and 13 µm. With a radiometric calibration of the...
InAs/GaSb superlattice focal plane arrays for high-resolution thermal imaging (2005)
Rehm, R., Walther, M., Schmitz, J., Fleißner, J., Fuchs, F., Ziegler, J., ...
The first fully operational mid-IR (3-5 µm) 256x256 IR-FPA camera system based on a type-II InAs/GaSb short-period superlattice showing an excellent noise equivalent temperature difference below 10...
Walther, M., Schmitz, J., Rehm, R., Kopta, S., Fuchs, F., Fleißner, J., ...
InAs/GaSb short-period superlattices (SLs) with a broken gap type-II band alignment are investigated for the fabrication of photovoltaic pin-photodetectors on GaSb substrates. The structures were...
Walther, M., Rehm, R., Fuchs, F., Schmitz, J., Fleißner, J., Cabanski, W., ...
An infrared camera based on a 256 x 256 focal plane array (FPA) for the second atmospheric window (3-5 µm) has been realized for the first time with InAs/GaSb short period superlattices (SLs). The...
Entwicklung eines Werkzeugs zur ressourcenorientierten Prozesskostenrechnung für die Logistik (2004)
3rd gen focal plane array IR detection modules and applications (2004)
Münzberg, M., Cabanski, W., Rode, W., Wendler, J., Ziegler, J., Eberhardt, K., ...
The 3rd generation of infrared (IR) detection modules is expected to provide video resolution or even more pixels and advanced functionalities like multicolor or multi band capability, higher frame...
Quantum cascade laser systems for gas analysis applications (2004)
Braun, M., Beyer, T., Hartwig, S., Plescher, G., Tauer, U., Lambrecht, A., ...
3rd gen focal plane array IR detection modules and applications (2004)
Cabanski, W., Eberhardt, K., Rode, W., Wendler, J., Ziegler, J., Fleißner, J., ...
The 3rd generation of infrared (IR) detection modules is expected to provide advanced features like higher resolution 1024x1024 or 1280x720 pixels and/or new functionalities like multicolor or multi...
Single-mode InP-based quantum cascade lasers for applications in trace-gas sensing (2004)
Mann, C., Yang, Q.K., Fuchs, F., Bronner, W., Köhler, K., Beyer, T., ...
State of the art 3rd gen IR detection modules in Germany (2004)
Cabanski, W., Rode, W., Wendler, J., Ziegler, J., Fleißner, J., Fuchs, F., ...
The 3rd generation of infrared (IR) detection modules is expected to provide advanced features like higher resolution 1024x1024 or 1280x720 pixels and/or new functions like multicolor or multi band...
Quantum Cascade lasers for the Mid-Infrared Spectral Range: Devices and Applications (2003)
Mann, C., Yang, Q. K., Fuchs, F., Bronner, W., Kiefer, R., Köhler, K., ...
InAs/(GaIn)Sb short period superlattices for IR detection (2003)
Fuchs, F., Schmitz, J., Pletschen, W., Koidl, P., Weimann, G.
InAs/(GaIn)Sb short-period superlattices (SL) grown by molecular-beam epitaxy (MBE) show a broken-gap type-II band alignment The effective band gap can be tailored ranging from the far-IR to the...
Continuous-wave operation of 5 µm quantum cascade lasers with high-reflection coated facets (2003)
Mann, C., Yang, Q.K., Fuchs, F., Bronner, W., Köhler, K.
A report is presented on the continuous-wave operation of lambda approximately=5 mu m GaInAs/AlInAs/InP-based quantum cascade lasers up to a heatsink temperature of 222 K (-51 degrees C). The devices...
Quantum cascade lasers for the mid-infrared spectral range: Devices and applications (2003)
Mann, C., Yang, Q.K., Fuchs, F., Bronner, W., Kiefer, R., Köhler, K., ...
Quantum cascade lasers emitting at lambda about 5 µm based on different active region designs are investigated. Using lattice-matched GaInAs/ AlInAs on InP substrates the maximum peak optical power...
Mid-infrared quantum cascade lasers operation above room temperature (2003)
Yang, Q.K., Mann, C., Fuchs, F., Kiefer, R., Köhler, K., Schneider, H.
Above room-temperature operation of lambda about 5 µm quantum cascade lasers with three different active regions is reported. Comparison between the three different designs, namely the conventional...
Yang, Q.K., Pfahler, C., Schmitz, J., Pletschen, W., Fuchs, F.
Trap centers and minority carrier lifetimes are investigated in InAs/(GaIn)Sb superlattices used for photodetectors in the far-infrared wavelength range. In our InAs/(GaIn)Sb superlattice...
Quantum cascade lasers with blocking barriers in the active regions (2002)
Mann, C., Yang, Q.K., Fuchs, F., Kiefer, R., Köhler, K., Schneider, H.
Yang, Q.K., Fuchs, F., Schmitz, J., Pletschen, W.
Trap centers with an energy level positioned 1/3 of the band gap below the effective conduction band edge are observed in the electroluminescence spectra of InAs/(Galn)Sb superlattice photodiodes...
Yang, Q.K., Mann, C., Fuchs, F., Kiefer, R., Köhler, K., Rollbühler, N., ...
We report the improvement of quantum cascade lasers emitting at lambda ~5 mu m by introducing AlAs blocking barriers together with strain- compensating InAs layers into the active regions. The...
Power efficiency of GaSb based 2.0 µm diode lasers (2001)
Rattunde, M., Mermelstein, C., Schmitz, J., Kiefer, R., Pletschen, W., Fuchs, F., ...
Rattunde, M., Mermelstein, C., Simanowski, S., Schmitz, J., Kiefer, R., Herres, N., ...
We report on the temperature dependence of threshold current for ridge waveguide. Ga(1-x)In(x)As(y)Sb(l-y)/Al(0.29)Ga(0.71)As(0.02)Sb(0.98) triple-QW diode lasers grown by MBE on GaSb. In and As...
Fuchs, F., Bürkle, L., Hamid, R., Herres, N., Pletschen, W., Sah, R. E., ...
The optoelectronic properties of short-period InAs/(GaIn)Sb superlattices (SLs) grown by molecular beam epitaxy on GaSb substrates are discussed. We report on the optimization of the SL materials...
Wannier-Stark localization in InAs/(GaIn)Sb superlattice diodes (2001)
Bürkle, L., Fuchs, F., Ahlswede, E., Pletschen, W., Schmitz, J.
We present experimental evidence for the formation of localized Wannier-Stark states in the depletion region of low band-gap InAs/(GaIn)Sb superlattice (SL) infrared photodiodes. In the photocurrent...
Thesis (Ph. D.)--Universitat des Saarlandes, 2001.
Bürkle, L., Fuchs, F., Kiefer, R., Pletschen, W., Sah, R. E., Schmitz, J.
InAs/(GaIn)Sb superlattice photodiodes with a cutoff wavelength of 8.7 mu m show a dynamic impedance of R(0)A = 1.5 k omega cm2 at 77 K and a responsivity of 2 A/W, corresponding to a detectivity of...
Growth of metastable GaAsSb for InP-based type-II emitters (2000)
Peter, M., Serries, D., Herres, N., Fuchs, F., Kiefer, R., Winkler, K., ...
We report on the growth of pseudomorphically strained, metastable GaAs(1-x)Sb(y) (0.22 <= y <= 0.7) films on InP using metal-organic chemical vapor deposition (MOCVD). The...
Control of the residual doping of InAs/(GaIn)Sb infrared superlattices (2000)
Bürkle, L., Fuchs, F., Schmitz, J., Pletschen, W.
Magnetotransport and photoluminescence (PL) measurements on InAs/(Galn)Sb superlattices (SLs) .grown by molecular-beam epitaxy on GaSb substrates at different substrate temperatures are reported....
Fuchs, F., Kemptner, E., Klement, D., Piepen, S. Van Der, Planta, K., ...
Der vorliegende Bericht beschreibt Einzelheiten der im Jahr 1997 durchgeführten theoretischen und experimentellen Untersuchungen, erzielte Ergebnisse, aufgetretene und zu erwartende Probleme bei der...
Mathematical Simulation of Bistatic RCS by Numerical and Analytical Methods (1999)
Fuchs, F., Kemptner, E., Klement, D., Planta, K.
Calculations of the bistatic RCS by computer codes based on FDTD, PO and IEM are compared with exact solutions and experimental results.
Peter, M., Kiefer, R., Fuchs, F., Herres, N., Winkler, K., Bachem, K.H., ...
We report on the fabrication and characterization of light-emitting diodes (LEDs) and laser diodes with a staggered type II Ga(1-x) In(x)As/GaAs(1-y)Sb(y) superlattice (SL) as the active region. SLs...
Fuchs, F., Bürkle, L., Pletschen, W., Schmitz, J., Walther, M., Güllich, H., ...
The structural properties of InAs/Ga(1-x)In(x)Sb infrared (IR) superlattice layers grown by MBE on GaSb substrates have been investigated using high-resolution X-ray diffraction, atomic force...
Peter, M., Herres, N., Fuchs, F., Winkler, K., Bachem, K.H., Wagner, J.
Metastable GaAs(1-y)Sb(y) with 0.22 < y < 0.70 has been grown pseudomorphically strained on (001) InP substrates using metalorganic chemical vapor deposition. The Sb concentration and layer...
Simanowski, S., Walther, M., Schmitz, J., Kiefer, R., Herres, N., Fuchs, F., ...
The incorporation of As and In during MBE growth in (AlGaIn)/(AsSb) layers used for the fabrication of diode lasers in the 2.0-2.5 mu m wavelength range has been investigated. The As content was...
The Solution of Differential Equations by the Method of Lie Series and Its Generalizations. (1998)
Grobner,W., Fuchs,F., Hairer,E., Kuhnert,K., Kastlunger,K.
As a part of the Lie Series, there is an operator D which operates on differentiable functions. A computer program to perform the differentiations automatically was prepared previously. A generalized...
The Method of Lie Series for Differential Equations and Its Extensions. (1998)
Wanner,G., Groebner,W., Fuchs,F., Hairer,E., Kirschner,O.
The work considers the initial value problem for an ordinary differential equation in a Banach space. The starting point of this research is Grobner's notation, the so-called Lie series. An explicit...
Dreher, K.H., Fuchs, F., Kemptner, E., Klement, D., Piepen, S. V. D., Preißner, J., ...
Der vorliegende Bericht beschreibt Einzelheiten der im Jahr 1997 durchgeführten theoretischen und experimentellen Untersuchungen, erzielte Ergebnisse, aufgetretene und zu erwartende Probleme bei der...
Spectroscopic ellipsometry for characterization of InAs/Ga(1-x)In(x)Sb superlattices (1998)
Wagner, J., Schmitz, J., Herres, N., Fuchs, F., Walther, M.
The pseudodielectric function of InAs/Ga(1-x)InxSb superlattices (SLs) grown by solid-source molecular-beam epitaxy, was measured by spectroscopic ellipsometry (SE) for photon energies ranging from...
Optical and electrical properties of InAs/Ga(1-x)In(x)Sb photodiodes for infrared detection (1998)
Fuchs, F., Pletschen, W., Weimar, U., Schmitz, J., Walther, M., Wagner, J., ...
We report on the fabrication and characterization of infrared photodiodes based on InAs/(GaIn)Sb superlattices grown on GaSb substrates. A series of devices employing a strain-optimized InAs/(GaIn)Sb...
Peter, M., Winkler, K., Herres, N., Fuchs, F., Müller, S., Bachem, K.H., ...
We report, on (Ga(1-x)In(x)As- GaAs(1-y)Sb(y)) superlattices grown strain-compensated on ( 100) InP:Fe substrates using new organic chemical vapor deposition. Low temperature photoluminescence...