@misc{WeisshauptSuergersBloosetal., author = {Weißhaupt, David and S{\"u}rgers, Christoph and Bloos, Dominik and Funk, Hannes Simon and Oehme, Michael and Fischer, Gerda and Schubert, Markus Andreas and Wenger, Christian and van Slageren, Joris and Fischer, Inga Anita and Schulze, J{\"o}rg}, title = {Lateral Mn5Ge3 spin-valve in contact with a high-mobility Ge two-dimensional hole gas}, series = {Semiconductor Science and Technology}, volume = {39}, journal = {Semiconductor Science and Technology}, number = {12}, publisher = {IOP Publishing}, issn = {0268-1242}, doi = {10.1088/1361-6641/ad8d06}, pages = {1 -- 10}, abstract = {Abstract Ge two-dimensional hole gases (2DHG) in strained modulation-doped quantum-wells represent a promising material platform for future spintronic applications due to their excellent spin transport properties and the theoretical possibility of efficient spin manipulation. Due to the continuous development of epitaxial growth recipes extreme high hole mobilities and low effective masses can be achieved, promising an efficient spin transport. Furthermore, the Ge 2DHG can be integrated in the well-established industrial complementary metal-oxide-semiconductor (CMOS) devices technology. However, efficient electrical spin injection into a Ge 2DHG—an essential prerequisite for the realization of spintronic devices—has not yet been demonstrated. In this work, we report the fabrication and low-temperature magnetoresistance (MR) measurements of a laterally structured Mn5Ge3/Ge 2DHG/ Mn5Ge3 device. The ferromagnetic Mn5Ge3 contacts are grown directly into the Ge quantum well by means of an interdiffusion process with a spacing of approximately 130 nm, forming a direct electrical contact between the ferromagnetic metal and the Ge 2DHG. Here, we report for the first time a clear MR signal for temperatures below 13 K possibly arising from successful spin injection into the high mobility Ge 2DHG. The results represent a step forward toward the realization of CMOS compatible spintronic devices based on a 2DHG.}, language = {en} } @misc{BochAllanBirkhoferetal., author = {Boch, Steffen and Allan, Eric and Birkhofer, Klaus and Bossdorf, Oliver and Bl{\"u}thgen, Nico and Christ-Breulmann, Sabina and Diek{\"o}tter, Tim and Dormann, Carsten F. and Gossner, Martin M. and Hallmann, Christine and Hemp, Andreas and H{\"o}lzel, Norbert and Jung, Kirsten and Klaus, Valentin H. and Klein, Alexandra M. and Kleinebecker, Till and Lange, Markus and M{\"u}ller, J{\"o}rg and Nacke, Heiko and Prati, Daniel and Renner, Swen C. and Rothenw{\"o}hrer, Christoph and Schall, Peter and Schulze, Ernst-Detlef and Socher, Stephanie A. and Tscharntke, Teja and T{\"u}rke, Manfred and Weiner, Christiane N. and Weisser, Wolfgang W. and Westphal, Catrin and Wolters, Volkmar and Wubet, Tesfaye and Fischer, Markus}, title = {Extensive und j{\"a}hrlich wechselnde Nutzungsintensit{\"a}t f{\"o}rdert den Artenreichtum im Gr{\"u}nland}, series = {ANLIEGEN NATUR}, volume = {38}, journal = {ANLIEGEN NATUR}, number = {1}, issn = {1864-0729}, pages = {86 -- 95}, language = {de} } @misc{HayatRatzkeAlvaradoChavarinetal., author = {Hayat, Ahsan and Ratzke, Markus and Alvarado Chavarin, Carlos and Z{\"o}llner, Marvin Hartwig and Corley-Wiciak, Agnieszka Anna and Schubert, Markus Andreas and Wenger, Christian and Fischer, Inga Anita}, title = {Structural and morphological properties of CeO2 films deposited by radio frequency magnetron sputtering for back-end-of-line integration}, series = {Thin Solid Films}, volume = {807}, journal = {Thin Solid Films}, issn = {0040-6090}, doi = {10.1016/j.tsf.2024.140547}, pages = {3}, language = {en} } @misc{HayatSpiritoCorleyWiciaketal., author = {Hayat, Ahsan and Spirito, Davide and Corley-Wiciak, Agnieszka Anna and Schubert, Markus Andreas and Masood, Maria and Reichmann, Felix and Ratzke, Markus and Capellini, Giovanni and Fischer, Inga Anita}, title = {MBE-based growth of Sn-rich quantum wells and dots at low Sn deposition rates}, series = {Materials Science in Semiconductor Processing}, volume = {165}, journal = {Materials Science in Semiconductor Processing}, issn = {1873-4081}, doi = {10.1016/j.mssp.2023.107693}, language = {en} } @misc{KalraAlvaradoChavarinNitschetal., author = {Kalra, Amanpreet and Alvarado Chavarin, Carlos and Nitsch, Paul-Gregor and Tschammer, Rudi and Flege, Jan Ingo and Ratzke, Markus and Zoellner, Marvin Hartwig and Schubert, Markus Andreas and Wenger, Christian and Fischer, Inga Anita}, title = {Deposition of CeOₓ/SnOₓ-based thin films via RF magnetron sputtering for resistive gas sensing applications}, series = {Physica B, Condensed matter}, volume = {723}, journal = {Physica B, Condensed matter}, publisher = {Elsevier BV}, address = {Amsterdam}, issn = {0921-4526}, doi = {10.1016/j.physb.2025.418098}, pages = {1 -- 7}, abstract = {Cerium oxide-tin oxide (CeOx/SnOx) thin films with varying Sn content were deposited using RF magnetron sputtering and investigated for hydrogen sensing applications. Structural, compositional, and morphological properties were characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). Gas sensing measurements showed effective hydrogen detection at room temperature, with the sensitivity strongly influenced by Sn content and oxygen vacancy concentration. Higher Sn concentration enhanced the sensing response, which was correlated with microstructural features obtained from AFM and EDX, as well as with the presence of Ce3+ and Ce4+ oxidation states identified by XPS. This study highlights the potential of CeOx/SnOx thin films for possible back-end-of-line integration and provides proof-of-principle for room-temperature hydrogen sensing.}, language = {en} } @misc{ZaplataWinterBiemeltetal., author = {Zaplata, Markus K. and Winter, S. and Biemelt, Detlef and Fischer, Annette}, title = {Colonization potential of the opportunistic herb Conyza canadensis at the landscape scale in an initial catchment}, language = {en} } @misc{FischerWeissWimmer, author = {Fischer, Alfons and Weiß, Sabine and Wimmer, Markus A.}, title = {The Tribological Difference between Biomedical Steels and CoCrMo-Alloys}, series = {Journal of the Mechanical Behavior of Biomedical Materials}, volume = {9}, journal = {Journal of the Mechanical Behavior of Biomedical Materials}, issn = {1878-0180}, pages = {50 -- 62}, language = {en} } @misc{ZaplataWinterBiemeltetal., author = {Zaplata, Markus K. and Winter, Susanne and Biemelt, Detlef and Fischer, Anton}, title = {Immediate shift towards source dynamics: The pioneer species Conyza canadensis in an initial ecosystem}, series = {Flora - Morphology, Distribution, Functional Ecology of Plants}, volume = {206}, journal = {Flora - Morphology, Distribution, Functional Ecology of Plants}, number = {11}, doi = {10.1016/j.flora.2011.07.001}, pages = {928 -- 934}, abstract = {The aim of this study was to detect a potential temporal shift from sink to source dynamics of pioneer plants during primary succession. The study was done in an initial ecosystem, namely an artificially constructed catchment on Pleistocene sands in eastern Germany. The import and export of seeds (including soil seed bank and seed rain), the development of vegetation cover and the population size of all pioneer species were recorded in 2005-2009. The interplay between the spatial distribution of seed rain and the prevailing wind direction provide evidence that seeds of Conyza canadensis (Asteraceae) first and to a considerable amount left the developing ecosystem. A change from a sink to source dynamics was detected already in the first year of both the existence of the site and occurrence of C. canadensis individuals within the site. Population patterns at the landscape unit scale demonstrated extensive auto-correlations in the coverage of this invasive plant at first. Our results underline the pioneer traits of C. canadensis as a prolific seeder and excellent wind disperser, which enables this species to become rapidly dominant over relatively large areas.}, language = {en} } @misc{ZaplataWinterFischeretal., author = {Zaplata, Markus K. and Winter, Susanne and Fischer, Anton and Kollmann, Johannes and Ulrich, Werner}, title = {Species-driven phases and increasing structure in early-successional plant communities}, series = {The American Naturalist}, volume = {Vol. 181}, journal = {The American Naturalist}, number = {1}, doi = {10.1086/668571}, pages = {E17 -- E27}, abstract = {Successional phases describe changes in ecological communities that proceed in steps rather than continuously. Despite their importance for the understanding of ecosystem development, there still exists no reliable definition of phases and no quantitative measure of phase transitions. In order to obtain these data, we investigated primary succession in an artificial catchment (6 ha) in eastern Germany over a period of 6 years. The data set consists of records of plant species and their cover values, and initial substrate properties, both from plots in a regular grid (20 m × 20 m) suitable for spatial data analysis. Community assembly was studied by analyses of species co-occurrence and nestedness. Additionally, we correlated lognormal and log series distributions of species abundance to each community. We here introduce a new general method for detection of successional phases based on the degree of transient spatial homogeneity in the study system. Spatially coherent vegetation patterns revealed non-overlapping partitions within this sequence of primary succession and were characterized as two distinct ecological phases. Patterns of species co-occurrence were increasingly less random, and hence the importance of demographic stochasticity and neutral community assembly decreased during the study period. Our findings highlight the spatial dimension of successional phases and quantify the degree of change between these steps. They are an element for advancing a more reliable terminology of ecological successions.}, language = {en} } @misc{WeinhardtFuchsFischeretal., author = {Weinhardt, Lothar and Fuchs, Oliver and Fischer, Andr{\´e} and Weigand, Markus and Meyer, Frank and Benkert, Andreas and Blum, Monika and B{\"a}r, Marcus and Pookpanratana, Sujitra and Denlinger, Jonathan D. and Heske, Clemens and Umbach, Eberhard}, title = {Site- and Symmetry-resolved Resonant X-ray Emission Study of a Highly-ordered PTCDA Thin Film}, series = {The Journal of Physical Chemistry: C}, volume = {120}, journal = {The Journal of Physical Chemistry: C}, number = {16}, issn = {1932-7447}, doi = {10.1021/acs.jpcc.5b12422}, pages = {8607 -- 8615}, language = {en} }