122 citations · 711 across the 26 of their papers we have counts for
18 papers · 1 filter
ScN/GaN(): a new platform for the epitaxy of twin-free metal-semiconductor heterostructures
Philipp John, Achim Trampert, Duc Van Dinh +6
We study the molecular beam epitaxy of rock-salt ScN on the wurtzite GaN() surface. To this end, ScN is grown on free-standing GaN() substrates and self-ass…
Optical properties of ScN layers grown on AlO(0001) by plasma-assisted molecular beam epitaxy
Duc V. Dinh, Frank Peiris, Jonas Lähnemann +1
An accurate knowledge of the optical constants (refractive index and extinction coefficient ) of ScN is crucial for understanding the optical properties of this binary nitri…
Growth kinetics and substrate stability during high-temperature molecular beam epitaxy of AlN nanowires
Philipp John, Mikel Gómez Ruiz, Len van Deurzen +5
We study the molecular beam epitaxy of AlN nanowires between 950 and 1215 °C, well above the usual growth temperatures, to identify optimal growth conditions. The nanowires are gro…
Lattice parameters of ScAlN layers grown on GaN(0001) by plasma-assisted molecular beam epitaxy
Duc V. Dinh, Jonas Lähnemann, Lutz Geelhaar +1
An accurate knowledge of the lattice parameters of the new nitride ScAlN is essential for understanding the elastic and piezoelectric properties of this…
Molecular beam epitaxy of single-crystalline bixbyite (InGa)O films (): Structural properties and consequences of compositional inhomogeneity
Alexandra Papadogianni, Charlotte Wouters, Robert Schewski +9
In this work, we show the heteroepitaxial growth of single-crystalline bixbyite (InGa)O films on (111)-oriented yttria-stabilized zirconia substrates using plas…
Bandgap widening and behavior of Raman-active phonon modes of cubic single-crystalline (In,Ga)O alloy films
Johannes Feldl, Martin Feneberg, Alexandra Papadogianni +5
The influence of Ga incorporation into cubic InO on the electronic and vibrational properties is discussed for (In,Ga)O alloy films grown by molecular b…
Carrier diffusion in GaN -- a cathodoluminescence study. III: Nature of nonradiative recombination at threading dislocations
Jonas Lähnemann, Vladimir M. Kaganer, Karl K. Sabelfeld +5
We investigate the impact of threading dislocations with an edge component (a or a+c-type) on carrier recombination and diffusion in GaN(0001) layers close to the surface as well a…
Carrier diffusion in GaN -- a cathodoluminescence study. II: Ambipolar vs. exciton diffusion
Oliver Brandt, Vladimir M. Kaganer, Jonas Lähnemann +8
We determine the diffusion length of excess carriers in GaN by spatially resolved cathodoluminescence spectroscopy utilizing a single quantum well as carrier collector or carrier s…
Carrier diffusion in GaN -- a cathodoluminescence study. I: Temperature-dependent generation volume
Uwe Jahn, Vladimir M. Kaganer, Karl K. Sabelfeld +8
The determination of the carrier diffusion length of semiconductors such as GaN and GaAs by cathodoluminescence imaging requires accurate knowledge about the spatial distribution o…
Self-assembly of well-separated AlN nanowires directly on sputtered metallic TiN films
Mani Azadmand, Tomas Auzelle, Jonas Lähnemann +7
We demonstrate the self-assembled formation of AlN nanowires by molecular beam epitaxy on sputtered TiN films on sapphire. This choice of substrate allows growth at an exceptionall…
Luminescent N-polar (In,Ga)N/GaN quantum wells grown by plasma-assisted molecular beam epitaxy at high temperature
C. Chèze, F. Feix, J. Lähnemann +6
N-polar (In,Ga)N/GaN quantum wells prepared on freestanding GaN substrates by plasma-assisted molecular beam epitaxy at conventional growth temperatures of about 650 °C do not exhi…
Hydride Vapor Phase Epitaxy of GaN on Silicon Covered by Nanostructures
U. Jahn, M. Musolino, J. Lähnemann +8
Several ten m GaN have been deposited on a silicon substrate using a two-step hydride vapor phase epitaxy (HVPE) process. The substrates have been covered by AlN layers and GaN…
Comparison of the luminous efficiency of Ga- and N-polar InGaN/InGaN quantum wells grown by plasma-assisted molecular beam epitaxy
Sergio Fernández-Garrido, Jonas Lähnemann, Christian Hauswald +5
We investigate the luminescence of Ga- and N-polar InGaN/InGaN quantum wells (QWs) grown by plasma-assisted molecular beam epitaxy on freestanding GaN a…
Localization and defects in axial (In,Ga)N/GaN nanowire heterostructures investigated by spatially-resolved luminescence spectroscopy
Jonas Lähnemann, Christian Hauswald, Martin Wölz +4
(In,Ga)N insertions embedded in self-assembled GaN nanowires are of current interest for applications in solid state light emitters. Such structures exhibit a notoriously broad emi…
Luminescence associated with stacking faults in GaN
Jonas Lähnemann, Uwe Jahn, Oliver Brandt +3
Basal-plane stacking faults are an important class of optically active structural defects in wurtzite semiconductors. The local deviation from the 2H stacking of the wurtzite matri…
Direct experimental determination of the spontaneous polarization of GaN
Jonas Lähnemann, Oliver Brandt, Uwe Jahn +8
We present a universal approach for determining the spontaneous polarization Psp of a wurtzite semiconductor from the emission energies of excitons bound to the different types of…
Coexistence of quantum-confined Stark effect and localized states in an (In,Ga)N/GaN nanowire heterostructure
Jonas Lähnemann, Oliver Brandt, Carsten Pfüller +7
We analyze the emission of single GaN nanowires with (In,Ga)N insertions using both micro-photoluminescence and cathodoluminescence spectroscopy. The emission spectra are dominated…
Epitaxial interfaces between crystallographically mismatched materials
Steven C. Erwin, Cunxu Gao, Claudia Roder +2
We report an unexpected mechanism by which an epitaxial interface can form between materials having strongly mismatched lattice constants. A simple model is proposed in which one m…