Lymperakis, L.: Surface rehybridization and strain effects on the composition and the properties of ternary III Nitride alloys. 19th International Conference on Crystal Growth and Epitaxy, Keystone, CO, USA (2019)
Lymperakis, L.: Elastically Frustrated Rehybridization: Implications in Alloy Ordering and Strong Compositional Limitations in Epitaxial InGaN Films. 1st German Austrian Conference of Crystal Growth, Vienna, Austria (2018)
Lymperakis, L.: Physics, growth mechanisms, and peculiarities of III-N surfaces from ab-initio. Seminar at Institute for solid state physics, Technical University Berlin, Berlin, Germany (2017)
Lymperakis, L.: Elastically frustrated rehybridization of InGaN surfaces: Implications on growth temperature and alloy ordering. Spring school on short period superlattices, Warsaw, Poland (2017)
Lymperakis, L.: Epitaxial Growth of III-Nitrides: Insights from Density Functional Theory Calculations. Seminar at University of Crete, Physics Department, Crete, Greece (2016)
Lymperakis, L.: Interplay of kinetics and thermodynamics of epitaxially grown wide bandgap semiconductors. 10th Asian-European Conference on Plasma Surface Engineering, Jeju Island, South Korea (2015)
Lymperakis, L.; Weidlich, P. H.; Eisele, H.; Schnedler, M.; Nys, J.-P.; Grandidier, B.; Stievenard, D.; Dunin-Borkowski, R.; Neugebauer, J.; Ebert, P.: Revealing Hidden Surface States of Non-Polar GaN Facets by an Ab Initio Tailored STM Approach. 10th International Conference on Nitride Semiconductors, Washigton DC, USA (2013)
Schulz, T.; Remmele, T.; Markurt, T.; Korytov, M.; Albrecht, M.; Duff, A.; Lymperakis, L.; Neugebauer, J.: Alloy fluctuations in III-Nitrides revisited by aberration corrected transmission electron microscopy. International Workshop on Nitride Semiconductors 2012, Sapporo, Japan (2012)
Lymperakis, L.: Ab initio calculations of energetics, adatom kinetics, and electronic structure of nonpolar and semipolar III-Nitride surfaces. PolarCoN Summer School, Kostanz, Germany (2012)
Albrecht, M.; Markurt, T.; Schulz, T.; Lymperakis, L.; Duff, A.; Neugebauer, J.; Drechsel, P.; Stauss, P.: Dislocation Mechanisms and Strain Relaxation in the Growth of GaN on Silicon Substrates for Solid State Lighting. International Conference on Extended Defects in Semiconductors, Thessaloniki, Greek (2012)
Lymperakis, L.; Albrecht, M.; Neugebauer, J.: Excitonic emission from a-type screw dislocations in GaN. International Conference on Extended Defects in Semiconductors, Thessaloniki, Greek (2012)
von Pezold, J.; Lymperakis, L.; Neugebauer, J.: Towards an ab-initio based understanding of H-embrittlement: An atomistic study of the HELP mechanism. Joint Hydrogenius and ICNER International Workshop on Hydrogen-Materials Interactions, Kyushu, Japan (2012)
Duff, A.; Lymperakis, L.; Neugebauer, J.: Ab-initio based comparitive study of In incorporation and surface segregation on III- and N-face {0001} InGaN surfaces. 9th International Conference of Nitride Semi-Conductors, Glasgow, UK (2011)
Hydrogen in aluminium can cause embrittlement and critical failure. However, the behaviour of hydrogen in aluminium was not yet understood. Scientists at the Max-Planck-Institut für Eisenforschung were able to locate hydrogen inside aluminium’s microstructure and designed strategies to trap the hydrogen atoms inside the microstructure. This can…
We plan to investigate the rate-dependent tensile properties of 2D materials such as metal thin films and PbMoO4 (PMO) films by using a combination of a novel plan-view FIB based sample lift out method and a MEMS based in situ tensile testing platform inside a TEM.
This project aims to investigate the influence of grain boundaries on mechanical behavior at ultra-high strain rates and low temperatures. For this micropillar compressions on copper bi-crystals containing different grain boundaries will be performed.
Oxidation and corrosion of noble metals is a fundamental problem of crucial importance in the advancement of the long-term renewable energy concept strategy. In our group we use state-of-the-art electrochemical scanning flow cell (SFC) coupled with inductively coupled plasma mass spectrometer (ICP-MS) setup to address the problem.
For understanding the underlying hydrogen embrittlement mechanism in transformation-induced plasticity steels, the process of damage evolution in a model austenite/martensite dual-phase microstructure following hydrogenation was investigated through multi-scale electron channelling contrast imaging and in situ optical microscopy.
We will investigate the electrothermomechanical response of individual metallic nanowires as a function of microstructural interfaces from the growth processes. This will be accomplished using in situ SEM 4-point probe-based electrical resistivity measurements and 2-point probe-based impedance measurements, as a function of mechanical strain and…
Hydrogen induced embrittlement of metals is one of the long standing unresolved problems in Materials Science. A hierarchical multiscale approach is used to investigate the underlying atomistic mechanisms.
Hydrogen embrittlement affects high-strength ferrite/martensite dual-phase (DP) steels. The associated micromechanisms which lead to failure have not been fully clarified yet. Here we present a quantitative micromechanical analysis of the microstructural damage phenomena in a model DP steel in the presence of hydrogen.
This project will aim at developing MEMS based nanoforce sensors with capacitive sensing capabilities. The nanoforce sensors will be further incorporated with in situ SEM and TEM small scale testing systems, for allowing simultaneous visualization of the deformation process during mechanical tests