@misc{LiRezaniaKammereretal., author = {Li, Chouyang and Rezania, Simin and Kammerer, Sarah and Sokolowski, Armin Andreas and Devaney, Trevor Thomas Joseph and Gorischek, Astrid and Jahn, Stephan Wenzel and Hackl, Hubert and Groschner, Klaus and Windpassinger, Christian and Malle, Ernst and Bauernhofer, Thomas and Schreibmayer, Wolfgang}, title = {Piezo1 forms mechanosensitive ion channels in the human MCF-7 breast cancer cell line}, series = {Scientific Reports}, volume = {5}, journal = {Scientific Reports}, issn = {2045-2322}, doi = {10.1038/srep08364}, pages = {9}, abstract = {Mechanical interaction between cells - specifically distortion of tensional homeostasis-emerged as an important aspect of breast cancer genesis and progression. We investigated the biophysical characteristics of mechanosensitive ion channels (MSCs) in the malignant MCF-7 breast cancer cell line. MSCs turned out to be the most abundant ion channel species and could be activated by negative pressure at the outer side of the cell membrane in a saturable manner. Assessing single channel conductance (GΛ) for different monovalent cations revealed an increase in the succession: Li⁺ < Na⁺ < K⁺ ≈Rb⁺ ≈ Cs⁺. Divalent cations permeated also with the order: Ca²⁺ < Ba²⁺. Comparison of biophysical properties enabled us to identify MSCs in MCF-7 as ion channels formed by the Piezo1 protein. Using patch clamp technique no functional MSCs were observed in the benign MCF-10A mammary epithelial cell line. Blocking of MSCs by GsMTx-4 resulted in decreased motility of MCF-7, but not of MCF-10A cells, underscoring a possible role of Piezo1 in invasion and metastatic propagation. The role of Piezo1 in biology and progression of breast cancer is further substantiated by markedly reduced overall survival in patients with increased Piezo1 mRNA levels in the primary tumor.}, language = {en} } @misc{RezaniaKammererLietal., author = {Rezania, Simin and Kammerer, Sarah and Li, Chouyang and Steinecker-Frohnwieser, Bibiane and Gorischek, Astrid and Devaney, Trevor Thomas Joseph and Verheyen, Sarah and Passegger, Christina and Ghaffari Tabrizi-Wizsy, Nassim and Hackl, Hubert and Platzer, Dieter and Zarnani, A.H. and Malle, Ernst and Jahn, Stephan Wenzel and Bauernhofer, Thomas and Schreibmayer, Wolfgang}, title = {Overexpression of KCNJ3 gene splice variants affects vital parameters of the malignant breast cancer cell line MCF-7 in an opposing manner}, series = {BMC Cancer}, volume = {16}, journal = {BMC Cancer}, issn = {1471-2407}, doi = {10.1186/s12885-016-2664-8}, abstract = {Background Overexpression the KCNJ3, a gene that encodes subunit 1 of G-protein activated inwardly rectifying K+ channel (GIRK1) in the primary tumor has been found to be associated with reduced survival times and increased lymph node metastasis in breast cancer patients. Methods In order to survey possible tumorigenic properties of GIRK1 overexpression, a range of malignant mammary epithelial cells, based on the MCF-7 cell line that permanently overexpress different splice variants of the KCNJ3 gene (GIRK1a, GIRK1c, GIRK1d and as a control, eYFP) were produced. Subsequently, selected cardinal neoplasia associated cellular parameters were assessed and compared. ResultsAdhesion to fibronectin coated surface as well as cell proliferation remained unaffected. Other vital parameters intimately linked to malignancy, i.e. wound healing, chemoinvasion, cellular velocities / motilities and angiogenesis were massively affected by GIRK1 overexpression. Overexpression of different GIRK1 splice variants exerted differential actions. While GIRK1a and GIRK1c overexpression reinforced the affected parameters towards malignancy, overexpression of GIRK1d resulted in the opposite. Single channel recording using the patch clamp technique revealed functional GIRK channels in the plasma membrane of MCF-7 cells albeit at very low frequency. DiscussionWe conclude that GIRK1d acts as a dominant negative constituent of functional GIRK complexes present in the plasma membrane of MCF-7 cells, while overexpression of GIRK1a and GIRK1c augmented their activity. The core component responsible for the cancerogenic action of GIRK1 is apparently presented by a segment comprising aminoacids 235-402, that is present exclusively in GIRK1a and GIRK1c, but not GIRK1d (positions according to GIRK1a primary structure). Conclusions The current study provides insight into the cellular and molecular consequences of KCNJ3 overexpression in breast cancer cells and the mechanism upon clinical outcome in patients suffering from breast cancer.}, language = {en} } @misc{HerrmannJahnMaurer, author = {Herrmann, Ludger and Jahn, Reinhold and Maurer, Thomas}, title = {Mineral dust around Sahara - from source to sink. A review with emphasis on contributions of the German soil science community in the last twenty years}, series = {Journal of Plant Nutrition and Soil Science}, volume = {173}, journal = {Journal of Plant Nutrition and Soil Science}, number = {6}, issn = {1522-2624}, pages = {811 -- 821}, language = {en} } @misc{BrinkmannHodačMohretal., author = {Brinkmann, Nicole and Hodač, Ladislav and Mohr, Kathrin I. and Hodačova, Alena and Jahn, Regine and Ramm, Jessica and Hallmann, Christine and Arp, Gernot and Friedl, Thomas}, title = {Cyanobacteria and diatoms in biofilms of two karstic streams in Germany and changes of their communities along calcite saturation gradients}, series = {Geomicrobiology Journal}, volume = {32}, journal = {Geomicrobiology Journal}, number = {3-4}, issn = {0149-0451}, doi = {10.1080/01490451.2014.901438}, pages = {255 -- 274}, language = {en} } @misc{JahnBlaudeckBaumannetal., author = {Jahn, Stephan F. and Blaudeck, Thomas and Baumann, Reinhard R. and Jakob, Alexander and Ecorchard, Petra and R{\"u}ffer, Tobias and Lang, Heinrich and Schmidt, Peer}, title = {Inkjet Printing of Conductive Silver Patterns by Using the First Aqueous Particle-Free MOD Ink without Additional Stabilizing Ligands}, series = {Chemistry of Materials}, volume = {22}, journal = {Chemistry of Materials}, number = {10}, issn = {1520-5002}, doi = {10.1021/cm9036428}, pages = {3067 -- 3071}, abstract = {The chemical and physical properties of [AgO2C(CH2OCH2)3H] (3) and its use as an aqueous, ligand-free MOD ink (MOD = metal-organic decomposition) for piezo inkjet printing is discussed. The printed, thermal, or photochemical sintered silver features are electrically conductive on glass (2.7 × 107 S m-1) and PET (PET = polyethylene terephthalate) substrates (1.1 × 107 S m-1) corresponding to 43\% and 18\% of the bulk silver conductivity. Conducted tape tests show the suitability of the ink for particularly polymer substrates. TG-MS studies demonstrate a two-step decomposition for the conversion of 3 to elemental silver. The structure of 3 in the solid state was determined by single X-ray structure determination.}, language = {en} } @misc{JahnJakobBlaudecketal., author = {Jahn, Stephan F. and Jakob, Alexander and Blaudeck, Thomas and Schmidt, Peer and Lang, Heinrich and Baumann, Reinhard R.}, title = {Inkjet printing of conductive patterns with an aqueous solution of [AgO2C(CH2OCH2)3H] without any additional stabilizing ligands}, series = {Thin Solid Films}, volume = {518}, journal = {Thin Solid Films}, number = {12}, issn = {0040-6090}, doi = {10.1016/j.tsf.2010.01.030}, pages = {3218 -- 3222}, abstract = {The use of silver(I)-2-[2-(2-methoxyethoxy)ethoxy]acetate, [AgO2C(CH2OCH2)3H], and its application as an aqueous metal-organic decomposition (MOD) inkjet ink is reported. The chemical and physical properties of the silver carboxylate and the ink formulated thereof are discussed. The ink meets all requirements of piezo driven inkjet printing. The printed features were converted into electrically conducting silver patterns by thermal or photo-thermal treatment. The conversion of [AgO2C(CH2OCH2)3H] to elemental silver follows a two-step decomposition as demonstrated by thermogravimetry-mass spectrometry (TG-MS) measurements. The measured conductivities of the printed features on glass and polyethylene-terephthalate (PET) are 2.7 × 107 S m-1 and 1.1 × 107 S m-1, respectively, which correspond to 43\% (glass) and 18\% (PET) of the bulk silver conductivity.}, language = {en} } @book{HirschlGriesshammerJahnetal., author = {Hirschl, Bernd and Grießhammer, Rainer and Jahn, Thomas and Hosang, Maik and Keil, Florian and Schr{\"o}der, Winfried and Walk, Heike}, title = {Klimaschutz erfordert Handeln - Beitr{\"a}ge der sozial-{\"o}kologischen Forschung}, publisher = {BMBF}, address = {Bonn [u.a.]}, pages = {34}, abstract = {Der Klimawandel hat Auswirkungen auf die Umwelt, die Menschen und ihre Lebensbedingungen, aber auch auf ihre Gestaltungsm{\"o}glichkeiten f{\"u}r die Zukunft. Die Bundesregierung hat deshalb klare und weit reichende Ziele f{\"u}r den Klimaschutz vorgegeben. Die Forschung mit ihren naturwissenschaftlich-technischen L{\"o}sungen und ihren gesellschaftswissenschaftlichen Erkenntnissen tr{\"a}gt zur Umsetzung dieser Ziele bei. Eine kohlenstofffreie Energiegewinnung und -nutzung zu f{\"o}rdern und weiterzuentwickeln sowie die vorhandenen Potenziale von energieeffizienten Techniken zu erschließen, kann einen entscheidenden Beitrag zur Senkung von Treibhausgasemissionen leisten. Verdeutlicht man sich jedoch die Herausforderungen, die mit dem Ziel einer Begrenzung des Temperaturanstiegs auf maximal zwei Grad verbunden sind, so ist unabweisbar, dass durch technologische Innovationen allein die Probleme des Klimawandels nicht gel{\"o}st werden k{\"o}nnen. Die Brosch{\"u}re "Klimaschutz erfordert Handeln" des Bundesministeriums f{\"u}r Bildung und Forschung zeigt Ergebnisse aus Forschungsvorhaben des F{\"o}rderschwerpunktes "Sozial-{\"o}kologische Forschung", die eine l{\"o}sungsorientierte Wissensbasis der dynamischen Wechselwirkungen zwischen Gesellschaften und ihrer nat{\"u}rlichen Umwelt geschaffen haben.}, language = {de} } @misc{SchneiderJahnDieterichetal., author = {Schneider, Erich and Jahn, Klaus and Dieterich, Marianne and Brandt, Thomas and Strupp, Michael}, title = {Gait deviations induced by visual stimulation in roll}, series = {Experimental Brain Research}, volume = {185}, journal = {Experimental Brain Research}, number = {1}, issn = {0014-4819}, doi = {10.1007/s00221-007-1134-6}, pages = {21 -- 26}, language = {en} } @misc{JahnNaesslSchneideretal., author = {Jahn, Klaus and Naeßl, Andrea and Schneider, Erich and Strupp, Michael and Brandt, Thomas and Dieterich, Marianne}, title = {Inverse u-shaped curve for age dependency of torsional eye movement responses to galvanic vestibular stimulation}, series = {Brain}, volume = {126}, journal = {Brain}, number = {7}, issn = {1460-2156}, doi = {10.1093/brain/awg163}, pages = {1579 -- 1589}, language = {en} } @misc{JahnNaesslStruppetal., author = {Jahn, Klaus and Naeßl, Andrea and Strupp, Michael and Schneider, Erich and Brandt, Thomas and Dieterich, Marianne}, title = {Torsional eye movement responses to monaural and binaural galvanic vestibular stimulation: side-to-side asymmetries.}, series = {Annals of the New York Academy of Sciences}, volume = {1004}, journal = {Annals of the New York Academy of Sciences}, issn = {0077-8923}, doi = {10.1111/j.1749-6632.2003.tb00265.x}, pages = {485 -- 489}, language = {en} } @misc{JahnStruppSchneideretal., author = {Jahn, Klaus and Strupp, Michael and Schneider, Erich and Dieterich, Marianne and Brandt, Thomas}, title = {Visually induced gait deviations during different locomotion speeds}, series = {Experimental Brain Research}, volume = {141}, journal = {Experimental Brain Research}, number = {3}, issn = {0014-4819}, doi = {10.1007/s002210100884}, pages = {370 -- 374}, language = {en} } @misc{JahnStruppSchneideretal., author = {Jahn, Klaus and Strupp, Michael and Schneider, Erich and Dieterich, Marianne and Brandt, Thomas}, title = {Differential effects of vestibular stimulation on walking and running}, series = {Neuroreport}, volume = {11}, journal = {Neuroreport}, number = {8}, issn = {1473-558X}, pages = {1745 -- 1748}, language = {en} } @misc{StruppGlasauerJahnetal., author = {Strupp, Michael and Glasauer, Stefan and Jahn, Klaus and Schneider, Erich and Krafczyk, Siegbert and Brandt, Thomas}, title = {Eye movements and balance}, series = {Annals of the New York Academy of Sciences}, volume = {1004}, journal = {Annals of the New York Academy of Sciences}, issn = {1749-6632}, pages = {352 -- 358}, language = {en} } @misc{KammererJahnWinteretal., author = {Kammerer, Sarah and Jahn, Stephan Wenzel and Winter, Elke and Eidenhammer, Sylvia and Rezania, Simin and Regitnig, Peter and Pichler, Martin and Schreibmayer, Wolfgang and Bauernhofer, Thomas}, title = {Critical evaluation of KCNJ3 gene product detection in human breast cancer: MRNA in situ hybridisation is superior to immunohistochemistry}, series = {Journal of Clinical Pathology}, volume = {69}, journal = {Journal of Clinical Pathology}, number = {12}, issn = {1472-4146}, doi = {10.1136/jclinpath-2016-203798}, pages = {1116 -- 1121}, abstract = {Increased expression levels of KCNJ3 have been correlated with lymph node metastases and poor prognosis in patients with breast cancer, suggesting a prognostic role of KCNJ3. We aimed to establish protocols for the detection of KCNJ3 in formalin-fixed, paraffin-embedded (FFPE) breast cancer tissue. Several antibodies were tested for sensitivity and specificity by western blot, followed by optimisation of the immunohistochemistry (IHC) procedure and establishment of KCNJ3 mRNA in situ hybridisation (ISH). Methods were validated by processing 15 FFPE breast cancer samples for which microarray data were available. Spearman's rank correlation analysis resulted in borderline significant correlation for IHC versus ISH (rS: 0.625; p<0.05) and IHC versus microarray (rS: 0.668; p<0.01), but in significant correlation for ISH versus microarray (rS: 0.861; p<0.001). The ISH method was superior to IHC, regarding robustness, sensitivity and specificity and will aid to further study expression levels of KCNJ3 in both malignant and physiological conditions.}, language = {en} } @misc{KammererSokolowskiHackletal., author = {Kammerer, Sarah and Sokolowski, Armin Andreas and Hackl, Hubert and Platzer, Dieter and Jahn, Stephan Wenzel and El-Heliebi, Amin and Schwarzenbacher, Daniela and Stiegelbauer, Verena and Pichler, Martin and Rezania, Simin and Fiegl, Heidelinde and Peintinger, Florentia and Regitnig, Peter and H{\"o}fler, Gerald and Schreibmayer, Wolfgang and Bauernhofer, Thomas}, title = {KCNJ3 is a new independent prognostic marker for estrogen receptor positive breast cancer patients}, series = {OncoTarget : open access impact journal}, volume = {7}, journal = {OncoTarget : open access impact journal}, number = {51}, doi = {10.18632/oncotarget.13224}, pages = {84705 -- 84717}, abstract = {Numerous studies showed abnormal expression of ion channels in different cancer types. Amongst these, the potassium channel gene KCNJ3 (encoding for GIRK1 proteins) has been reported to be upregulated in tumors of patients with breast cancer and to correlate with positive lymph node status. We aimed to study KCNJ3 levels in different breast cancer subtypes using gene expression data from the TCGA, to validate our findings using RNA in situ hybridization in a validation cohort (GEO ID GSE17705), and to study the prognostic value of KCNJ3using survival analysis. In a total of > 1000 breast cancer patients of two independent data sets we showed a) that KCNJ3 expression is upregulated in tumor tissue compared to corresponding normal tissue (p < 0.001), b) that KCNJ3 expression is associated with estrogen receptor (ER) positive tumors (p < 0.001), but that KCNJ3 expression is variable within this group, and c) that ER positive patients with high KCNJ3 levels have worse overall (p < 0.05) and disease free survival probabilities (p < 0.01), whereby KCNJ3 is an independent prognostic factor (p <0.05). In conclusion, our data suggest that patients with ER positive breast cancer might be stratified into high risk and low risk groups based on the KCNJ3 levels in the tumor.}, language = {en} } @misc{HeuserSchulzSağlametal., author = {Heuser, Fabian and Schulz, Christian and Sağlam, Murat and Ramaioli, Cecilia and Heuberger, Maria and Wagner, Klaus J. and Jahn, Klaus and Schneider, Erich and Brandt, Thomas and Glasauer, Stefan and Lehnen, Nadine}, title = {Preventing opioid-induced nausea and vomiting: Rest your head and close your eyes?}, series = {PloS one}, volume = {12}, journal = {PloS one}, number = {3}, issn = {1932-6203}, doi = {10.1371/journal.pone.0173925}, pages = {e0173925}, language = {en} } @misc{SpiegelClaassenTeufeletal., author = {Spiegel, Rainer and Claassen, Jens and Teufel, Julian and Bardins, Stanislav and Schneider, Erich and Lehrer, Nicole and Jahn, Klaus and Anciaes da Silva, F{\´a}bio and Hahn, Ales and Farahmand, Parvis and Brandt, Thomas and Strupp, Michael and Kalla, Roger}, title = {Resting in darkness improves downbeat nystagmus: evidence from an observational study}, series = {Annals of the New York Academy of Sciences}, volume = {1375}, journal = {Annals of the New York Academy of Sciences}, number = {1}, issn = {1749-6632}, doi = {10.1111/nyas.13172}, pages = {66 -- 73}, abstract = {Resting in an upright position during daytime decreases downbeat nystagmus (DBN). When measured in brightness only, that is, without intermitting exposure to darkness, it does not make a significant difference whether patients have previously rested in brightness or in darkness. In real-world scenarios, people are often exposed to brightness and darkness intermittently. The aim of this study was to analyze whether resting in brightness or resting in darkness was associated with a lower post-resting DBN after intermitting exposures to brightness and darkness. Eight patients were recorded with three-dimensional video-oculography in brightness and darkness conditions, each following two 2-h resting intervals under either brightness or darkness resting conditions. The dependent variable was DBN intensity, measured in mean slow phase velocity. A repeated measures ANOVA with the factors measurement condition (brightness vs. darkness), resting condition (brightness vs. darkness), and time (after first vs. second resting interval) showed a significant effect for the factor resting condition, where previous resting in darkness was associated with a significantly lower DBN relative to previous resting in brightness (P < 0.01). The clinical relevance is to advise patients with DBN to rest in darkness.}, language = {en} } @misc{AubeleGrillEggertetal., author = {Aubele, Maria and Grill, Eva and Eggert, Thomas and Schneider, Erich and Strobl, Ralf and Jahn, Klaus and M{\"u}ller, Martin and Holle, Rolf and Linkohr, Birgit and Heier, Margit and Ladwig, Karl-Heinz and Lehnen, Nadine}, title = {Symptoms in unilatral vestibular hypofunction are associated with number of catch-up saccades and retinal errors: results from the population-based KORA FF4study}, series = {Frontiers in Neurology}, volume = {2023}, journal = {Frontiers in Neurology}, number = {14}, issn = {1664-2295}, pages = {8}, abstract = {Objective: The presence and intensity of symptoms vary in patients with unilateral vestibular hypofunction. We aimed to determine which saccadic and vestibulo-ocular reflex parameters best predict the presence of symptoms in unilateral vestibular hypofunction in order to better understand vestibular compensation and its implications for rehabilitation therapy. Methods: Video head impulse test data were analyzed from a subpopulation of 23 symptomatic and 10 currently symptom-free participants with unilateral vestibular hypofunction, embedded in the KORA (Cooperative Health Research in the Region of Augsburg) FF4 study, the second follow-up of the KORA S4 population-based health survey (2,279 participants). Results: A higher number of catch-up saccades, a higher percentage of covert saccades, and a larger retinal error at 200 ms after the onset of the head impulse were associated with relevant symptoms in participants with unilateral vestibular hypofunction (p = 0.028, p = 0.046, and p = 0.038, respectively). After stepwise selection, the number of catch-up saccades and retinal error at 200 ms remained in the final logistic regression model, which was significantly better than a null model (p = 0.014). Age, gender, saccade amplitude, saccade latency, and VOR gain were not predictive of the presence of symptoms. Conclusion: The accuracy of saccadic compensation seems to be crucial for the presence of symptoms in unilateral vestibular hypofunction, highlighting the role of specific gaze stabilization exercises in rehabilitation. Early saccades, mainly triggered by the vestibular system, do not seem to compensate accurately enough, resulting in a relevant retinal error and the need for more as well as more accurate catch-up saccades, probably triggered by the visual system.}, language = {en} } @misc{SchoeberlPradhanIrvingetal., author = {Sch{\"o}berl, Florian and Pradhan, Cauchy and Irving, Stephanie and Buerger, Katharina and Xiong, Guoming and Kugler, G{\"u}nter and Kohlbecher, Stefan and Engmann, Julia and Werner, Philipp and Brendel, Matthias and Schneider, Erich and Perneczky, Robert and Jahn, Klaus and Foug{\`e}re, Christian la and Bartenstein, Peter and Brandt, Thomas and Dietrich, Marianne and Zwergal, Andreas}, title = {Real-space navigation testing differentiates between amyloid-positive and -negative aMCI}, series = {Neurology : official journal of the American Academy of Neurology}, volume = {94}, journal = {Neurology : official journal of the American Academy of Neurology}, number = {8}, issn = {1526-632X}, doi = {10.1212/WNL.0000000000008758}, pages = {e861 -- e873}, language = {en} } @misc{GonzalezMerinoJahnPolyanskiietal., author = {Gonz{\´a}lez Merino, Bernardo and Jahn, Thomas and Polyanskii, Alexander and Wachsmuth, Gerd}, title = {Hunting for Reduced Polytopes}, series = {Discrete \& Computational Geometry}, volume = {60}, journal = {Discrete \& Computational Geometry}, number = {3}, issn = {0179-5376}, doi = {10.1007/s00454-018-9982-3}, pages = {801 -- 808}, abstract = {We show that there exist reduced polytopes in three-dimensional Euclidean space. This partially answers the question posed by Lassak (Israel J Math 70(3):365-379, 1990) on the existence of reduced polytopes in d-dimensional Euclidean space for d≥3.}, language = {en} } @book{HirschlGriesshammerJahnetal., author = {Hirschl, Bernd and Grießhammer, Rainer and Jahn, Thomas and Hosang, Maik and Keil, Florian and Schr{\"o}der, Winfried and Walk, Heike}, title = {Climate protection demands action - Contributions Made by Social-Ecological Research}, publisher = {BMBF}, address = {Bonn [u.a.]}, pages = {40}, abstract = {Climate change impacts on the environment, people and their living conditions but also for on their possibilities for shaping their future. The Federal Government has therefore set clear and far-reaching targets for combating climate change. With its scientific technical solutions and sociological knowledge, research contributes to the implementation of these goals. Promoting and developing the carbon-free generation and use of energy as well as tapping existing potentials of energy-efficient technologies can make a decisive contribution to reducing greenhouse gas emissions. But if one looks at the challenges linked to the goal of limiting the rise in temperature to a maximum of two degrees, it is quite obvious that the problems of climate change cannot be solved through technological innovation alone. The brochure "Climate protection needs action", published by the Federal Ministry for Education and Research, shows results from research projects conducted under the support measure "socio-ecological research" which have created a solution-oriented knowledge base about the dynamic interactions between societies and their natural environment.}, language = {en} } @misc{StrobelAlvaradoChavarinVoelkeletal., author = {Strobel, Carsten and Alvarado Chavarin, Carlos and V{\"o}lkel, Sandra and Jahn, Andreas and Hiess, Andre and Knaut, Martin and Albert, Matthias and Wenger, Christian and Steinke, Olaff and Stephan, Ulf and R{\"o}hlecke, S{\"o}ren and Mikolajick, Thomas}, title = {Enhanced Electrical Properties of Optimized Vertical Graphene-Base Hot Electron Transistors}, series = {ACS Applied Electronic Materials}, volume = {5}, journal = {ACS Applied Electronic Materials}, number = {3}, issn = {2637-6113}, doi = {10.1021/acsaelm.2c01725}, pages = {1670 -- 1675}, abstract = {The arrival of high-mobility two-dimensional materials like graphene leads to the renaissance of former vertical semiconductor-metal-semiconductor (SMS) hot electron transistors. Because of the monolayer thickness of graphene, improved SMS transistors with a semimetallic graphene-base electrode are now feasible for high-frequency applications. In this study we report about a device that consists of amorphous silicon, graphene, and crystalline silicon. For the first time, this device is fabricated by a four-mask lithography process which leads to significant improvements in the device performance. A strongly increased common-emitter current gain of 2\% could be achieved while the on-off ratio improved to 1.6 × 105, which is already higher than predicted theoretically. This could be mainly attributed to better interface characteristics and decreased lateral dimensions of the devices. A cutoff frequency of approximately 26 MHz could be forecasted based on the DC measurements of the device.}, language = {en} } @misc{StrobelAlvaradoChavarinRichteretal., author = {Strobel, Carsten and Alvarado Chavarin, Carlos and Richter, Karola and Knaut, Martin and Reif, Johanna and Völkel, Sandra and Jahn, Andreas and Albert, Matthias and Wenger, Christian and Kirchner, Robert and Bartha, Johann Wolfgang and Mikolajick, Thomas}, title = {Novel Graphene Adjustable-Barrier Transistor with Ultra-High Current Gain}, series = {ACS Applied Materials \& Interfaces}, volume = {14}, journal = {ACS Applied Materials \& Interfaces}, number = {34}, issn = {1944-8244}, doi = {10.1021/acsami.2c10634}, pages = {39249 -- 39254}, abstract = {A graphene-based three terminal barristor device was proposed to overcome the low on/off ratios and insufficient current saturation of conventional graphene field effect transistors. In this study, we fabricated and analyzed a novel graphene-based transistor, which resembles the structure of the barristor but uses a different operating condition. This new device, termed graphene adjustable-barriers transistor (GABT), utilizes a semiconductor-based gate rather than a metal-insulator gate structure to modulate the device currents. The key feature of the device is the two graphene-semiconductor Schottky barriers with different heights that are controlled simultaneously by the gate voltage. Due to the asymmetry of the barriers, the drain current exceeds the gate current by several orders of magnitude. Thus, the GABT can be considered an amplifier with an alterable current gain. In this work, a silicon-graphene-germanium GABT with an ultra-high current gain (ID/IG up to 8 × 106) was fabricated, and the device functionality was demonstrated. Additionally, a capacitance model is applied to predict the theoretical device performance resulting in an on-off ratio above 106, a swing of 87 mV/dec, and a drivecurrent of about 1 × 106 A/cm2.}, language = {en} }