Leo, Karl

Falkenberg Christiane; Leo Karl; Riede Moritz K.

Improved photocurrent by using n-doped 2,3,8,9,14,15-hexachloro-5,6,11,12,17,18-hexaazatrinaphthylene as optical spacer layer in p-i-n type organic solar cells

Meiss Jan; Holzmueller Felix; Gresser Roland; Leo Karl; Riede Moritz

Near-infrared absorbing semitransparent organic solar cells

Schwab Tobias; Thomschke Michael; Hofmann Simone; Furno Mauro; Leo Karl; Lüssem Björn

Efficiency enhancement of top-emitting organic light-emitting diodes using conversion dyes

Falkenberg Christiane; Leo Karl; Riede Moritz K.

Improved photocurrent by using n-doped 2,3,8,9,14,15-hexachloro-5,6,11,12,17,18-hexaazatrinaphthylene as optical spacer layer in p-i-n type organic solar cells

Meiss Jan; Holzmueller Felix; Gresser Roland; Leo Karl; Riede Moritz

Near-infrared absorbing semitransparent organic solar cells

Schwab Tobias; Thomschke Michael; Hofmann Simone; Furno Mauro; Leo Karl; Lüssem Björn

Efficiency enhancement of top-emitting organic light-emitting diodes using conversion dyes

Sebastian P.; Lindner F.; Walzer K.; Lüssem B.; Leo K.

Investigation on the origin of the memory effect in metal/organic semiconductor/metal structures

Schober M.; Anderson M.; Thomschke M.; Widmer J.; Furno M.; Scholz R.; Lüssem B.; Leo K.

Quantitative description of charge-carrier transport in a white organic light-emitting diode

Elschner Chris; Levin Alexandr; Wilde Lutz; Grenzer Jörg; Schroer Christian; Leo Karl; Riede Moritz

Determining the C60 molecular arrangement in thin films by means of X-ray diffraction

Kasemann D.; Brückner R.; Fröb H.; Leo K.

Organic light-emitting diodes under high currents explored by transient electroluminescence on the nanosecond scale

Hyun Kim Yong; Sachse Christoph; Hermenau Martin; Fehse Karsten; Riede Moritz; Müller-Meskamp Lars; Leo Karl

Improved efficiency and lifetime in small molecule organic solar cells with optimized conductive polymer electrodes

Lee Jonghee; Hofmann Simone; Thomschke Michael; Furno Mauro; Hyun Kim Yong; Lüssem Björn; Leo Karl

Highly efficient bi-directional organic light-emitting diodes by strong micro-cavity effects

Ray Debdutta; Furno Mauro; Siebert-Henze Ellen; Leo Karl; Riede Moritz

Quantitative estimation of electronic quality of zinc phthalocyanine thin films

Lee Jonghee; Hofmann Simone; Thomschke Michael; Furno Mauro; Kim Yong Hyun; Lüssem Björn; Leo Karl

Increased and balanced light emission of transparent organic light-emitting diodes by enhanced microcavity effects

de Moraes Ines Rabelo; Scholz Sebastian; Lüssem Björn; Leo Karl

Role of oxygen-bonds in the degradation process of phosphorescent organic light emitting diodes

Meiss Jan; Menke Torben; Leo Karl; Uhrich Christian; Gnehr Wolf-Michael; Sonntag Stefan; Pfeiffer Martin; Riede Moritz

Highly efficient semitransparent tandem organic solar cells with complementary absorber materials

Brückner R.; Sudzius M.; Fröb H.; Lyssenko V. G.; Leo K.

Saturation of laser emission in a small mode volume organic microcavity

Meerheim Rico; Olthof Selina; Hermenau Martin; Scholz Sebastian; Petrich Annette; Tessler Nir; Solomeshch Olga; Lüssem Björn; Riede Moritz; Leo Karl

Investigation of C60F36 as low-volatility p-dopant in organic optoelectronic devices

Lee Jonghee; Hofmann Simone; Furno Mauro; Thomschke Michael; Kim Yong Hyun; Lüssem Björn; Leo Karl

Influence of organic capping layers on the performance of transparent organic light-emitting diodes

Meiss Jan; Hermenau Martin; Tress Wolfgang; Schuenemann Christoph; Selzer Franz; Hummert Markus; Alex Joerg; Lackner Gerhard; Leo Karl; Riede Moritz

Tetrapropyl-tetraphenyl-diindenoperylene derivative as a green absorber for high-voltage stable organic solar cells

Thomschke Michael; Hofmann Simone; Olthof Selina; Anderson Merve; Kleemann Hans; Schober Matthias; Lüssem Björn; Leo Karl

Improvement of voltage and charge balance in inverted top-emitting organic electroluminescent diodes comprising doped transport layers by thermal annealing

Tress Wolfgang; Petrich Annette; Hummert Markus; Hein Moritz; Leo Karl; Riede Moritz

Imbalanced mobilities causing S-shaped IV curves in planar heterojunction organic solar cells

Brückner R.; Sudzius M.; Hintschich S. I.; Fröb H.; Lyssenko V. G.; Leo K.

Hybrid optical Tamm states in a planar dielectric microcavity

Hofmann Simone; Thomschke Michael; Freitag Patricia; Furno Mauro; Lüssem Björn; Leo Karl

Top-emitting organic light-emitting diodes: Influence of cavity design

Meerheim Rico; Furno Mauro; Hofmann Simone; Lüssem Björn; Leo Karl

Quantification of energy loss mechanisms in organic light-emitting diodes

Rosenow Thomas C.; Furno Mauro; Reineke Sebastian; Olthof Selina; Lüssem Björn; Leo Karl

Highly efficient white organic light-emitting diodes based on fluorescent blue emitters

Haase J.; Shinohara S.; Mundra P.; Risse G.; Lyssenko V. G.; Fröb H.; Hentschel M.; Eychmüller A.; Leo K.

Hemispherical resonators with embedded nanocrystal quantum rod emitters

Ray Debdutta; Burtone Lorenzo; Leo Karl; Riede Moritz

Detection of trap charge in small molecular organic bulk heterojunction solar cells

Wynands D.; Levichkova M.; Leo K.; Uhrich C.; Schwartz G.; Hildebrandt D.; Pfeiffer M.; Riede M.

Increase in internal quantum efficiency in small molecular oligothiophene: C60 mixed heterojunction solar cells by substrate heating

Timmreck Ronny; Olthof Selina; Leo Karl; Riede Moritz K.

Highly doped layers as efficient electron–hole recombination contacts for tandem organic solar cells

Seifert Ruben; Scholz Sebastian; Lüssem Björn; Leo Karl

Comparison of ultraviolet- and charge-induced degradation phenomena in blue fluorescent organic light emitting diodes

Schober Matthias; Olthof Selina; Furno Mauro; Lüssem Björn; Leo Karl

Single carrier devices with electrical doped layers for the characterization of charge-carrier transport in organic thin-films

Wünsche J.; Reineke S.; Lüssem B.; Leo K.

Measurement of triplet exciton diffusion in organic light-emitting diodes

Meiss Jan; Furno Mauro; Pfuetzner Steffen; Leo Karl; Riede Moritz

Selective absorption enhancement in organic solar cells using light incoupling layers

Seidler Nico; Reineke Sebastian; Walzer Karsten; Lüssem Björn; Tomkeviciene Ausra; Grazulevicius Juozas V.; Leo Karl

Influence of the hole blocking layer on blue phosphorescent organic light-emitting devices using 3,6-di(9-carbazolyl)-9-(2-ethylhexyl)carbazole as host material

Schueppel Rico; Timmreck Ronny; Allinger Nikola; Mueller Toni; Furno Mauro; Uhrich Christian; Leo Karl; Riede Moritz

Controlled current matching in small molecule organic tandem solar cells using doped spacer layers

Wynands D.; Levichkova M.; Riede M.; Pfeiffer M.; Baeuerle P.; Rentenberger R.; Denner P.; Leo K.

Correlation between morphology and performance of low bandgap oligothiophene:C60 mixed heterojunctions in organic solar cells

Meiss Jan; Leo Karl; Riede Moritz K.; Uhrich Christian; Gnehr Wolf-Michael; Sonntag Stefan; Pfeiffer Martin

Efficient semitransparent small-molecule organic solar cells

Olthof S.; Tress W.; Meerheim R.; Lüssem B.; Leo K.

Photoelectron spectroscopy study of systematically varied doping concentrations in an organic semiconductor layer using a molecular p-dopant

Siebert-Henze E.; Langner M.; Sudzius M.; Hintschich S. I.; Fröb H.; Lyssenko V. G.; Leo K.

Polarization splitting of discrete states in square shaped organic photonic dots

Becker F.; Langner M.; Fröb H.; Lyssenko V. G.; Leo K.; Adachi C.

Dependence of polarization splitting on mode tuning in microcavities

Scholz Sebastian; Lüssem Björn; Leo Karl

Chemical changes on the green emitter tris(8-hydroxy-quinolinato)aluminum during device aging of p-i-n-structured organic light emitting diodes

Hong Z. R.; Lessmann R.; Maennig B.; Huang Q.; Harada K.; Riede M.; Leo K.

Antenna effects and improved efficiency in multiple heterojunction photovoltaic cells based on pentacene, zinc phthalocyanine, and C60

Wynands David; Reinold Egon; Brier Eduard; Leo Karl; Riede Moritz; Männig Bert; Bäuerle Peter

Organic thin film photovoltaic cells based on planar and mixed heterojunctions between fullerene and a low bandgap oligothiophene

Langner M.; Sudzius M.; Fröb H.; Lyssenko V. G.; Leo K.

Selective excitation of laser modes in an organic photonic dot microcavity

Meiss Jan; Leo Karl; Falkenberg Christiane; Allinger Nikola; Riede Moritz

Transparent conductive layers for organic solar cells: simulation and experiment

Pfuetzner Steffen; Meiss Jan; Petrich Annette; Riede Moritz; Leo Karl

Thick C60:ZnPc bulk heterojunction solar cells with improved performance by film deposition on heated substrates

Olthof S.; Schober M.; Meerheim R.; Leo K.

Energy level alignment at the interfaces in a multilayer organic light-emitting diode structure

Pfuetzner Steffen; Meiss Jan; Petrich Annette; Riede Moritz; Leo Karl

Improved bulk heterojunction organic solar cells employing C70 fullerenes

Reineke Sebastian; Schwartz Gregor; Walzer Karsten; Falke Meiken; Leo Karl

Highly phosphorescent organic mixed films: The effect of aggregation on triplet-triplet annihilation

Meiss Jan; Riede Moritz K.; Leo Karl

Optimizing the morphology of metal multilayer films for indium tin oxide (ITO)-free inverted organic solar cells

Thomschke Michael; Nitsche Robert; Furno Mauro; Leo Karl

Optimized efficiency and angular emission characteristics of white top-emitting organic electroluminescent diodes

Sudzius M.; Langner M.; Hintschich S. I.; Lyssenko V. G.; Fröb H.; Leo K.

Multimode laser emission from laterally confined organic microcavities

Scholz Sebastian; Meerheim Rico; Lüssem Björn; Leo Karl

Laser desorption/ionization time-of-flight mass spectrometry: A predictive tool for the lifetime of organic light emitting devices

Meiss J.; Riede M. K.; Leo K.

Towards efficient tin-doped indium oxide (ITO)-free inverted organic solar cells using metal cathodes

Lindner Frank; Walzer Karsten; Leo Karl

Organic heterostructure device with nonvolatile memory behavior using electrically doped layers

Scholz Sebastian; Huang Qiang; Thomschke Michael; Olthof Selina; Sebastian Philipp; Walzer Karsten; Leo Karl; Oswald Steffen; Corten Cathrin; Kuckling Dirk

Self-doping and partial oxidation of metal-on-organic interfaces for organic semiconductor devices studied by chemical analysis techniques

Harada Kentaro; Riede Moritz; Leo Karl; Hild Olaf R.; Elliott C. Michael

Erratum: Pentacene homojunctions: Electron and hole transport properties and related photovoltaic responses [Phys. Rev. B ;77, 195212 (2008)]

Schulze Kerstin; Riede Moritz; Brier Eduard; Reinold Egon; Bäuerle Peter; Leo Karl

Dicyanovinyl-quinquethiophenes with varying alkyl chain lengths: Investigation of their performance in organic devices

Holzhey A.; Uhrich C.; Brier E.; Reinhold E.; Bäuerle P.; Leo K.; Hoffmann M.

Exciton diffusion and energy transfer in organic solar cells based on dicyanovinyl-terthiophene

Meiss J.; Allinger N.; Riede M. K.; Leo K.

Improved light harvesting in tin-doped indum oxide (ITO)-free inverted bulk-heterojunction organic solar cells using capping layers

Fehse Karsten; Meerheim Rico; Walzer Karsten; Leo Karl; Lövenich Wilfried; Elschner Andreas

Lifetime of organic light emitting diodes on polymer anodes

Schwartz Gregor; Ke Tung-Huei; Wu Chung-Chih; Walzer Karsten; Leo Karl

Balanced ambipolar charge carrier mobility in mixed layers for application in hybrid white organic light-emitting diodes

Uhrich Christian; Wynands David; Olthof Selina; Riede Moritz K.; Leo Karl; Sonntag Stefan; Maennig Bert; Pfeiffer Martin

Origin of open circuit voltage in planar and bulk heterojunction organic thin-film photovoltaics depending on doped transport layers

Falkenberg Christiane; Uhrich Christian; Olthof Selina; Maennig Bert; Riede Moritz K.; Leo Karl

Efficient p-i-n type organic solar cells incorporating 1,4,5,8-naphthalenetetracarboxylic dianhydride as transparent electron transport material

Meerheim Rico; Nitsche Robert; Leo Karl

High-efficiency monochrome organic light emitting diodes employing enhanced microcavities

Meerheim Rico; Scholz Sebastian; Olthof Selina; Schwartz Gregor; Reineke Sebastian; Walzer Karsten; Leo Karl

Influence of charge balance and exciton distribution on efficiency and lifetime of phosphorescent organic light-emitting devices

Harada Kentaro; Hild Olaf R.; Leo Karl; Riede Moritz; Elliott C. Michael

Pentacene homojunctions: Electron and hole transport properties and related photovoltaic responses

Schütte B.; Gothe H.; Hintschich S. I.; Sudzius M.; Fröb H.; Lyssenko V. G.; Leo K.

Continuously tunable laser emission from a wedge-shaped organic microcavity

Riede Moritz K.; Mueller Toni; Maennig Bert; Leo Karl; Sylvester-Hvid Kristian O.; Zimmermann Birger; Niggemann Michael; Gombert Andreas

Comment on “Roles of donor and acceptor nanodomains in 6% efficient thermally annealed polymer photovoltaics” [Appl. Phys. Lett. ;90, 163511 (2007)]

Schueppel R.; Schmidt K.; Uhrich C.; Schulze K.; Wynands D.; Brédas J. L.; Brier E.; Reinold E.; Bu H.-B.; Baeuerle P.; Maennig B.; Pfeiffer M.; Leo K.

Optimizing organic photovoltaics using tailored heterojunctions: A photoinduced absorption study of oligothiophenes with low band gaps

Rosenow Thomas Conrad; Walzer Karsten; Leo Karl

Near-infrared organic light emitting diodes based on heavy metal phthalocyanines

Schwartz Gregor; Reineke Sebastian; Walzer Karsten; Leo Karl

Reduced efficiency roll-off in high-efficiency hybrid white organic light-emitting diodes

Langner M.; Gehlhaar R.; Schriever C.; Fröb H.; Lyssenko V. G.; Leo K.

Strong optical confinement and multimode emission of organic photonic dots

Fehse Karsten; Olthof Selina; Walzer Karsten; Leo Karl; Johnson Robert L.; Glowatzki Hendrik; Bröker Benjamin; Koch Norbert

Energy level alignment of electrically doped hole transport layers with transparent and conductive indium tin oxide and polymer anodes

Reineke Sebastian; Schwartz Gregor; Walzer Karsten; Leo Karl

Reduced efficiency roll-off in phosphorescent organic light emitting diodes by suppression of triplet-triplet annihilation

Harada Kentaro; Li Fenghong; Maennig Bert; Pfeiffer Martin; Leo Karl

Ionized impurity scattering in n-doped C60 thin films

Schulze Kerstin; Maennig Bert; Leo Karl; Tomita Yuto; May Christian; Hüpkes Jürgen; Brier Eduard; Reinold Egon; Bäuerle Peter

Organic solar cells on indium tin oxide and aluminum doped zinc oxide anodes

Tomita Yuto; May Christian; Toerker Michael; Amelung Joerg; Eritt Michael; Loeffler Frank; Luber Claus; Leo Karl; Walzer Karsten; Fehse Karsten; Huang Qiang

Highly efficient p-i-n-type organic light emitting diodes on ZnO:Al substrates

Schneeweiss P.; Sudzius M.; Gehlhaar R.; Hoffmann M.; Lyssenko V. G.; Fröb H.; Leo K.

Observation of Kastler ring stimulated emission from an organic microcavity

Fehse Karsten; Schwartz Gregor; Walzer Karsten; Leo Karl

Combination of a polyaniline anode and doped charge transport layers for high-efficiency organic light emitting diodes

Hong Z. R.; Maennig B.; Lessmann R.; Pfeiffer M.; Leo K.; Simon P.

Improved efficiency of zinc phthalocyanine/C60 based photovoltaic cells via nanoscale interface modification

Staroske W.; Pfeiffer M.; Leo K.; Hoffmann M.

Single-Step Triplet-Triplet Annihilation: An Intrinsic Limit for the High Brightness Efficiency of Phosphorescent Organic Light Emitting Diodes

Reineke Sebastian; Walzer Karsten; Leo Karl

Triplet-exciton quenching in organic phosphorescent light-emitting diodes with Ir-based emitters

Huang Qiang; Reineke Sebastian; Walzer Karsten; Pfeiffer Martin; Leo Karl

Quantum efficiency enhancement in top-emitting organic light-emitting diodes as a result of enhanced intrinsic quantum yield

Neyts Kristiaan; Marescaux Matthias; Nieto Angel Ullan; Elschner Andreas; Lövenich Wilfried; Fehse Karsten; Huang Qiang; Walzer Karsten; Leo Karl

Inhomogeneous luminance in organic light emitting diodes related to electrode resistivity

Swoboda M.; Gehlhaar R.; Sudzius M.; Hoffmann M.; Fröb H.; Lyssenko V. G.; Leo K.

Terahertz beating of laser emission from an organic microcavity

Huang Qiang; Walzer Karsten; Pfeiffer Martin; Leo Karl; Hofmann Michael; Stübinger Thomas

Performance improvement of top-emitting organic light-emitting diodes by an organic capping layer: An experimental study

Schwartz Gregor; Fehse Karsten; Pfeiffer Martin; Walzer Karsten; Leo Karl

Highly efficient white organic light emitting diodes comprising an interlayer to separate fluorescent and phosphorescent regions

Meerheim Rico; Walzer Karsten; Pfeiffer Martin; Leo Karl

Ultrastable and efficient red organic light emitting diodes with doped transport layers

Li Fenghong; Pfeiffer Martin; Werner Ansgar; Harada Kentaro; Leo Karl; Hayashi Naoki; Seki Kazuhiko; Liu Xianjie; Dang Xuan-Dung

Acridine orange base as a dopant for n doping of C60 thin films

Engel E.; Schmidt K.; Beljonne D.; Brédas J.-L.; Assa J.; Fröb H.; Leo K.; Hoffmann M.

Transient absorption spectroscopy and quantum-chemical studies of matrix-isolated perylene derivatives

Levichkova M. M.; Assa J. J.; Fröb H.; Leo K.

Blue luminescent isolated Alq3 molecules in a solid-state matrix

Huang Qiang; Walzer Karsten; Pfeiffer Martin; Lyssenko Vadim; He Gufeng; Leo Karl

Highly efficient top emitting organic light-emitting diodes with organic outcoupling enhancement layers

Gehlhaar R.; Swoboda M.; Sudzius M.; Hoffmann M.; Fröb H.; Lyssenko V. G.; Leo K.; Wendrock H.

Polarization splitting and terahertz oscillations from a single planar Fabry-Pérot microcavity

Koschorreck M.; Gehlhaar R.; Lyssenko V. G.; Swoboda M.; Hoffmann M.; Leo K.

Dynamics of a high-Q vertical-cavity organic laser

Engel E.; Koschorreck M.; Leo K.; Hoffmann M.

Ultrafast Relaxation in Quasi-One-Dimensional Organic Molecular Crystals

Fanciulli R.; Weiner A. M.; Dignam M. M.; Meinhold D.; Leo K.

Coherent Control of Bloch Oscillations by Means of Optical Pulse Shaping

Drechsel J.; Männig B.; Kozlowski F.; Pfeiffer M.; Leo K.; Hoppe H.

Efficient organic solar cells based on a double p-i-n architecture using doped wide-gap transport layers

Proehl Holger; Nitsche Robert; Leo Karl; Dienel Thomas; Fritz Torsten

In situ differential reflectance spectroscopy of thin crystalline films of PTCDA on different substrates

Fanciulli R.; Weiner A. M.; Dignam M. M.; Meinhold D.; Leo K.

Coherent control of Bloch oscillations by means of optical pulse shaping

Mannsfeld Stefan C. B.; Leo Karl; Fritz Torsten

Line-on-Line Coincidence: A New Type of Epitaxy Found in Organic-Organic Heterolayers

Harada K.; Werner A. G.; Pfeiffer M.; Bloom C. J.; Elliott C. M.; Leo K.

Organic Homojunction Diodes with a High Built-in Potential: Interpretation of the Current-Voltage Characteristics by a Generalized Einstein Relation

Rosam B.; Leo K.; Yang L.; Dignam M. M.

Terahertz generation by difference-frequency mixing of exciton Wannier–Stark ladder states in biased semiconductor superlattices

He Gufeng; Pfeiffer Martin; Leo Karl; Hofmann Michael; Birnstock Jan; Pudzich Robert; Salbeck Josef

High-efficiency and low-voltage p‐i‐n; electrophosphorescent organic light-emitting diodes with double-emission layers

He Gufeng; Pfeiffer Martin; Zhou Xiang; Qin Dashan; Schneider Oliver; Leo Karl

Very high-efficiency and low voltage phosphorescent organic light-emitting diodes based on a p-i-n junction

Yang Lijun; Rosam Ben; Lachaine Jean-Marc; Leo Karl; Dignam M. M.

Intraband polarization and terahertz emission in biased semiconductor superlattices with full excitonic basis

Holfeld C. P.; Schäfer W.; Leo K.

Carrier dynamics and intraminiband coupling in semiconductor superlattices

Rosam B.; Zimmer F.; Korsch H. J.; Keck F.; Glück M.; Leo K.; Köhler K.

Lifetime of Wannier-Stark states in semiconductor superlattices under strong Zener tunneling to above-barrier bands

Werner A. G.; Li F.; Harada K.; Pfeiffer M.; Fritz T.; Leo K.

Pyronin B as a donor for n-type doping of organic thin films

Huang Jingsong; Blochwitz-Nimoth Jan; Pfeiffer Martin; Leo Karl

Influence of the thickness and doping of the emission layer on the performance of organic light-emitting diodes with PiN structure

Zhou X.; Qin D. S.; Pfeiffer M.; Blochwitz-Nimoth J.; Werner A.; Drechsel J.; Maennig B.; Leo K.; Bold M.; Erk P.; Hartmann H.

High-efficiency electrophosphorescent organic light-emitting diodes with double light-emitting layers

Zhou X.; Pfeiffer M.; Huang J. S.; Blochwitz-Nimoth J.; Qin D. S.; Werner A.; Drechsel J.; Maennig B.; Leo K.

Low-voltage inverted transparent vacuum deposited organic light-emitting diodes using electrical doping

Knupfer M.; Schwieger T.; Fink J.; Leo K.; Hoffmann M.

Excitons in quasi-one-dimensional organic crystals

Meinhold D.; Leo K.; Fromer N. A.; Chemla D. S.; Glutsch S.; Bechstedt F.; Köhler K.

Zener tunneling in superlattices in a magnetic field

Meinhold D.; Rosam B.; Löser F.; Lyssenko V. G.; Rossi F.; Zhang Jian-Zhong; Köhler K.; Leo K.

Polarization revival of a Bloch-oscillating wave packet in conjunction with resonant Zener tunneling

Huang Jingsong; Pfeiffer Martin; Werner Ansgar; Blochwitz Jan; Leo Karl; Liu Shiyong

Low-voltage organic electroluminescent devices using pin structures

Maennig B.; Pfeiffer M.; Nollau A.; Zhou X.; Leo K.; Simon P.

Controlled p-type doping of polycrystalline and amorphous organic layers: Self-consistent description of conductivity and field-effect mobility by a microscopic percolation model

Huang Jingsong; Pfeiffer Martin; Blochwitz Jan; Werner Ansgar; Salbeck Josef; Liu Shiyong; Leo Karl

Low Operating Voltage and High Efficiency Organic Multilayer Electroluminescent Devices with p‐Type Doped Hole Injection Layer

Werner A. G.; Blochwitz J.; Pfeiffer M.; Leo K.

Field dependence of thermally stimulated currents in Alq3

Proehl Holger; Toerker Michael; Sellam Farid; Simpson Christopher; Leo Karl; Fritz Torsten; Müllen Klaus

Comparison of ultraviolet photoelectron spectroscopy and scanning tunneling spectroscopy measurements on highly ordered ultrathin films of hexa-peri-hexabenzocoronene on Au(111)

Glutsch S.; Bechstedt F.; Rosam B.; Leo K.

Zener tunneling effect of excitons in shallow superlattices

Rosam B.; Meinhold D.; Löser F.; Lyssenko V. G.; Glutsch S.; Bechstedt F.; Rossi F.; Köhler K.; Leo K.

Field-Induced Delocalization and Zener Breakdown in Semiconductor Superlattices

Zhou X.; Pfeiffer M.; Blochwitz J.; Werner A.; Nollau A.; Fritz T.; Leo K.

Very-low-operating-voltage organic light-emitting diodes using a p-doped amorphous hole injection layer

Löser F.; Dignam M. M.; Kosevich Yu. A.; Köhler K.; Leo K.

Self-Induced Shapiro Effect in Semiconductor Superlattices

Nollau A.; Hoffmann M.; Floreck K.; Fritz T.; Leo K.

A simple measurement of the absolute internal quantum efficiency of thin organic films

Löser F.; Köhler K.; Kosevich Yu. A.; Leo K.

Dynamics of Bloch oscillations under the influence of scattering and coherent plasmon coupling

Nollau A.; Fritz T.; Pfeiffer M.; Leo K.

Controlled n-type doping of a molecular organic semiconductor: Naphthalenetetracarboxylic dianhydride (NTCDA) doped with bis(ethylenedithio)-tetrathiafulvalene (BEDT-TTF)

Djuriŝić Aleksandra B.; Fritz Torsten; Leo Kral; Li E. Herbert

Improved method for determination of optical constants of organic thin films from reflection and transmission measurements

Pfeiffer M.; Beyer A.; Fritz T.; Leo K.

Erratum: “Controlled doping of phthalocyanine layers by cosublimation with acceptor molecules; A systematic seebeck and conductivity study” [Appl. Phys. Lett. ;73, 3202 (1998)]

Usami N.; Leo K.; Shiraki Y.

Optical characterization of strain-induced structural modification in SiGe-based heterostructures

Sudzius M.; Lyssenko V. G.; Valusis G.; Löser F.; Hasche T.; Leo K.; Dignam M. M.; Köhler K.

Measurement and control of the spatial amplitude of Bloch oscillations in semiconductor superlattices

Pfeiffer M.; Beyer A.; Fritz T.; Leo K.

Controlled doping of phthalocyanine layers by cosublimation with acceptor molecules: A systematic Seebeck and conductivity study

Blochwitz J.; Pfeiffer M.; Fritz T.; Leo K.

Low voltage organic light emitting diodes featuring doped phthalocyanine as hole transport material

Holfeld C. P.; Löser F.; Sudzius M.; Leo K.; Whittaker D. M.; Köhler K.

Fano Resonances in Semiconductor Superlattices

Sudzius M.; Lyssenko V. G.; Löser F.; Leo K.; Dignam M. M.; Köhler K.

Optical control of Bloch-oscillation amplitudes: From harmonic spatial motion to breathing modes

Rebohle L.; von Borany J.; Yankov R. A.; Skorupa W.; Tyschenko I. E.; Fröb H.; Leo K.

Strong blue and violet photoluminescence and electroluminescence from germanium-implanted and silicon-implanted silicon-dioxide layers

Lyssenko V. G.; Valušis G.; Löser F.; Hasche T.; Leo K.; Dignam M. M.; Köhler K.

Direct Measurement of the Spatial Displacement of Bloch-Oscillating Electrons in Semiconductor Superlattices

Zott S.; Leo K.; Ruckh M.; Schock H.-W.

Radiative recombination in CuInSe2 thin films

Schmitz-Hübsch T.; Fritz T.; Sellam F.; Staub R.; Leo K.

Epitaxial growth of 3,4,9,10-perylene-tetracarboxylic-dianhydride on Au(111): A STM and RHEED study

Pfeiffer M.; Leo K.; Karl N.

Fermi level determination in organic thin films by the Kelvin probe method

Puech K.; Zott S.; Leo K.; Ruckh M.; Schock H.-W.

Determination of minority carrier lifetimes in CuInSe2 thin films

Puech K.; Fröb H.; Hoffman M.; Leo K.

Luminescence of ultrathin organic films: transition from monomer to excimer emission

Skorupa W.; Yankov R. A.; Tyschenko I. E.; Fröb H.; Böhme T.; Leo K.

Room‐temperature, short‐wavelength (400–500 nm) photoluminescence from silicon‐implanted silicon dioxide films

Zott S.; Leo K.; Ruckh M.; Schock H.-W.

Photoluminescence of polycrystalline CuInSe2 thin films

Leisching P.; Leo K.; Schäfer W.; Kurz H.; Beck W.; Köhler K.

External field‐dependent enhancement of internal Coulomb interactions in time‐resolved four‐wave mixing

Leisching P.; Haring Bolivar P.; Beck W.; Dhaibi Y.; Brüggemann F.; Schwedler R.; Kurz H.; Leo K.; Köhler K.

Bloch oscillations of excitonic wave packets in semiconductor superlattices

Hunsche S.; Leo K.; Kurz H.; Köhler K.

Femtosecond intersubband relaxation in GaAs quantum wells

Hunsche S.; Leo K.; Kurz H.; Köhler K.

Exciton absorption saturation by phase‐space filling; Influence of carrier temperature and density

Bakker Huib J.; Shah Jagdeep; Leo Karl; Köhler Klaus

Time‐resolved study of dephasing mechanisms of excitons in GaAs/Al;xGa1-;xAs quantum‐well structures

Heesel H.; Hunsche S.; Mikkelsen H.; Dekorsy T.; Leo K.; Kurz H.

Dynamics of electric field screening in a bulk GaAs modulator

Kersting R.; Lemmer U.; Mahrt R. F.; Leo K.; Kurz H.; Bässler H.; Göbel E. O.

Femtosecond energy relaxation in π‐conjugated polymers

Waschke Christian; Kurz Heinrich; Leo Karl; Schwedler Ralf; Roskos Hartmut G.; Köhler Klaus

Coherent submillimeter‐wave emission from Bloch oscillations in a semiconductor superlattice

Kersting R.; Plettner J.; Leo K.; Averin S.; Kurz H.

Time‐resolved luminescence study of ultrafast carrier transport in GaAs metal‐semiconductor‐metal devices

Zettler J.-Th.; Mikkelsen H.; Leo K.; Kurz H.; Carius R.; Förster A.

Modulated ellipsometric measurements and transfer‐matrix calculation of the field‐dependent dielectric function of a multiple quantum well

Damen Theodore C.; Vina Luis; Leo Karl; Cunningham John E.; Shah Jagdeep; Sham Lu J.

Spin relaxation dynamics of excitons and free carriers in quasi-two-dimensional GaAlAs/GaAs structures

Schmitt-Rink Stefan; Bennhardt Dirk; Heuckeroth Volker; Thomas Peter; Haring Peter; Maidorn Gerd; Bakker Huib; Leo Karl; Kim Dai-Sik; Shah Jagdeep; Köhler Klaus

Polarization dependence of heavy‐ and light‐hole quantum beats

Feldmann J.; Cunningham J. E.; Thomas P.; Schulze A.; von Plessen G.; Meier T.; Miller D. A. B.; Shah J.; Leo K.; Schmitt-Rink S.

Optical investigation of Bloch oscillations in a semiconductor superlattice

Kersting R.; Schwedler R.; Wolter K.; Leo K.; Kurz H.

Dynamics of carrier transport and carrier capture in In1-;xGaxAs/InP heterostructures

Roskos Hartmut G.; Nuss Martin C.; Shah Jagdeep; Schmitt-Rink Stefan; Fox A. Mark; Miller David A. B.; Leo Karl; Köhler Klaus

Coherent submillimeter‐wave emission from charge oscillations in a double‐well potential

Zhou X. Q.; Leo K.; Kurz H.

Ultrafast relaxation of photoexcited holes in n‐doped III‐V compounds studied by femtosecond luminescence

Leo K.; Göbel E. O.; Damen T. C.; Müller J. F.; Köhler K.; Schmitt-Rink S.; Schäfer W.; Shah J.; Ganser P.

Subpicosecond four‐wave mixing in GaAs/Al;xGa1-;xAs quantum wells

Schmitt-Rink Stefan; Mukamel Shaul; Leo Karl; Shah Jagdeep; Chemla Daniel S.

Stochastic theory of time‐resolved four‐wave mixing in interacting media

Damen T. C.; Leo Karl; Shah Jagdeep; Cunningham J. E.

Spin relaxation and thermalization of excitons in GaAs quantum wells

Leo Karl; Shah Jagdeep; Göbel Ernst O.; Damen Theodore C.; Schmitt-Rink Stefan; Schäfer Wilfried; Köhler Klaus

Coherent oscillations of a wave packet in a semiconductor double‐quantum‐well structure

Leo Karl; Damen Theo C.; Shah Jagdeep; Köhler Klaus

Quantum beats of free and bound excitons in GaAs/AlxGa1-;xAs quantum wells

Leo Karl; Shah Jagdeep; Gordon J. P.; Damen T. C.; Miller D. A. B.; Tu C. W.; Cunningham J. E.

Effect of collisions and relaxation on coherent resonant tunneling: Hole tunneling in GaAs/AlxGa1-;xAs double‐quantum‐well structures

Leo Karl; Shah Jagdeep; Gordon James P.; Damen Theodore C.; Miller David A. B.; Tu Charles W.; Cunningham John E.; Henry Jill E.

Hole tunneling in GaAs/AlGaAs heterostructures: coherent versus incoherent resonant tunneling

Leo K.; Wegener M.; Shah J.; Chemla D. S.; Göbel E. O.; Damen T. C.; Schmitt-Rink S.; Schäfer W.

Effects of coherent polarization interactions on time‐resolved degenerate four‐wave mixing

Leo Karl; Damen Theo C.; Shah Jagdeep; Göbel Ernst O.; Köhler Klaus

Quantum beats of light hole and heavy hole excitons in quantum wells

Leo Karl; Göbel Ernst O.; Shah Jagdeep; Damen Theo C.; Köhler Klaus; Ganser Peter

Tunneling in semiconductor heterostructures studied by subpicosecond four‐wave mixing

Göbel E. O.; Leo K.; Damen T. C.; Shah J.; Schmitt-Rink S.; Schäfer W.; Müller J. F.; Köhler K.

Quantum beats of excitons in quantum wells