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- Research Data8x8 Patch-Antenna-Coupled TeraFET Detector Array for Terahertz Quantum-Cascade-Laser Applications2024-04-10North, Nicholas K.Horbury, Michael D.Kondawar, SanchitKundu, ImanSalih, MohammedKrysl, AnastasiyaLi, LianheLinfield, Edmund H.Freeman, Joshua R.Valavanis, AlexanderLisauskas, AlvydasRoskos, Hartmut G.Monolithically integrated, antenna-coupled field-effect transistors (TeraFETs) represent sensitive and fast detectors operable at room temperature, designed to detect radiation across the terahertz range (0.3~THz to 10~THz). For this study, we conducted an experimental characterization of a single monolithically integrated patch-antenna coupled TeraFET optimized for maximum sensitivity at 3.4~THz. This characterization utilized a single-mode high-power terahertz Quantum-Cascade-Laser (QCL) emitting at the designated frequency. Subsequently, we integrated 8x8 of the aforementioned monolithically integrated patch-antenna-coupled TeraFET elements into a parallel readout circuitry, facilitated by the process maturity of a commercial 65-nm process node. This configuration, referred to as the "multi-element" terahertz detector, stands in contrast to conventional detector matrices where each TeraFET represents a pixel. Here, the entire TeraFET network operates as a unified pixel, amalgamating the output signals of all rectifying elements. For the multi-element detector presented here, we emphasize two significant enhancements for sensitive power detection experiments involving a 2.85~THz and a 3.4~THz single-mode quantum-cascade laser (QCL). First, the larger effective detector area improves detector alignment and signal stability with regards to vibrations. Additionally, the 8x8 array configuration provides a significantly reduced source-drain resistance of approximately 300~$\Omega$ at the most sensitive working bias point, which is determined to be at a gate-source bias of approx. 0.6~V in case of the single element. The decreased load impedance results in a substantial reduction in (thermal) detector noise and an increase in the attainable modulation bandwidth, particularly when coupled with a low-noise voltage amplifier circuit. Building upon the introduced approaches, we present a TeraFET-based detector system implementation that achieves a -3~dB modulation bandwidth of 15~MHz around the most sensitive bias point, with the potential to extend up to 20~MHz by further reducing detector impedance through adjustments in the applied gate potential (as depicted in \autoref{fig:RDS_noise_analysis}). Finally, we validate the system's performance using high-resolution spectroscopy data to investigating methanol vapor around 3.4~THz.
4 56 - Research DataA j_eff 12 Kitaev material on the triangular lattice: The case of NaRuO22023-06-07Motivated by recent reports of a quantum disordered ground state in the triangular lattice compound NaRuO$_2$, we derive a $j_{\rm eff}=1/2$ magnetic model for this system by means of first-principles calculations. The pseudospin Hamiltonian is dominated by bond-dependent off-diagonal $\Gamma$ interactions, complemented by a ferromagnetic Heisenberg exchange and a notably \emph{antiferromagnetic} Kitaev term. In addition to bilinear interactions, we find a sizable four-spin ring exchange contribution with a \emph{strongly anisotropic} character, which has been so far overlooked when modeling Kitaev materials. The analysis of the magnetic model, based on the minimization of the classical energy and exact diagonalization of the quantum Hamiltonian, points toward the existence of a rather robust easy-plane ferromagnetic order, which cannot be easily destabilized by physically relevant perturbations.
309 33 - Research DataAb initio study of highly tunable charge transfer in β-RuCl3/graphene heterostructures2024-06-25Heterostructures of graphene in proximity to magnetic insulators open the possibility to investigate exotic states emerging from the interplay of magnetism, strain and charge transfer between the layers. Recent reports on the growth of self-integrated atomic wires of $\beta$-RuCl$_3$ on graphite suggest these materials as versatile candidates to investigate these effects. Here we present detailed first principles calculations on the charge transfer and electronic structure of $\beta$-RuCl$_3$/graphene heterostructures and provide a comparison with the work function analysis of the related honeycomb family members $\alpha$-RuX$_3$ (X = Cl,Br,I). We find that proximity of the two layers leads to a hole-doped graphene and electron-doped RuX$_3$ in all cases, which is sensitively dependent on the distance between the two layers. Furthermore, strain effects due to lattice mismatch control the magnetization which itself has a strong effect on the charge transfer. Charge accumulation in $\beta$-RuCl$_3$ strongly drops away from the chain making such heterostructures suitable candidates for sharp interfacial junctions in graphene-based devices.
6 - Research DataAl-Mudhaybi Regional Survey: Field photos of the structures2023-09Edelmann, Pascal (DataCollector)Hofmann, Andreas (DataCollector)Hochrieser, Stefanie (DataCollector)Möbius, Merle (DataCollector)Maiorano, Maria Pia (DataCollector)Biezeveld, Irini (DataCollector)Billor, Beriwan (DataCollector)Grün, Fabian (DataCollector)Kluge, Jonas (DataCollector)Koch, Katharina (DataCollector)Mez, Nathalie (DataCollector)Schneider, Tamara (DataCollector)Zöchling, Antje (DataCollector)Juhas, Marcel (DataCollector)Özcelik, Taylan (DataCollector)Puerta-Schardt, Juan-Marco (DataCollector)Schweizer, Moyra (DataCollector)Schmidt, Conrad (DataCollector)Göbel, Jonas (DataCollector)Budzyn, Adrian (DataCollector)Werner, Jannis (DataCollector)Öztürk, Mahsa (DataCollector)Greven, Sofia (DataCollector)The Al-Mudhaybi Regional Survey was initiated to gain insights into settlement patterns, their development, and the causes of significant social changes in Central Oman, particularly during the 3rd millennium BCE. This was achieved through a combination of survey methods (remote sensing based on satellite imagery with ground-truthing and intensive systematic surveys in north-south transects) as well as small-scale excavations. The results challenged the previous notion of traditional settlement hierarchies and a predominantly sedentary, agriculture-based society in Central Oman, especially during the Early Bronze Age (Umm an-Nar period). In-stead, a complex network of temporary sites emerged, utilized at various times and for different activities. Another significant finding is that the interior of Oman was more heavily frequented during the Neolithic period than previously believed. Additionally, contrary to prior assumptions, the Middle Bronze Age (Wadi Suq period) does not represent a period of decline and shares similarities in its development with the northern regions of the Omani Peninsula. These findings can contribute to raising awareness of the diversity of human lifestyles overall, particularly highlighting the cultural achievements of mobile communities.
94 51 - Research DataClimate forcing GSWP3-ERA5 as input for the global hydrological model WaterGAP2024-06-19This dataset contains the climate data for the 4 variables (pr, tas, rsds, rlds) to run the Python-Version of WaterGAP. For details please see the ReWaterGAP documentation (https://hydrologyfrankfurt.github.io/ReWaterGAP/).
26 2 - Research DataColossal magnetoresistance in EuZn2P2 and its electronic and magnetic structure2023-07-12We investigate single crystals of the trigonal antiferromagnet EuZn2P2 (P-3m1) by means of electrical trans- port, magnetization measurements, x-ray magnetic scattering, optical reflectivity, angle-resolved photoemission spectroscopy (ARPES), and ab initio band structure calculations (DFT + U ). We find that the electrical resistivity of EuZn2P2 increases strongly upon cooling and can be suppressed in magnetic fields by several orders of magnitude (colossal magnetoresistance effect). Resonant magnetic scattering reveals a magnetic ordering vector of q = (0 0 1/2 ), corresponding to an A-type antiferromagnetic order, below TN = 23.7 K. We find that the moments are canted out of the a-a plane by an angle of about 40° ± 10° and aligned along the [100] direction in the a-a plane. We observe nearly isotropic magnetization behavior for low fields and low temperatures which is consistent with the magnetic scattering results. The magnetization measurements show a deviation from the Curie-Weiss behavior below ≈150 K, the temperature below which also the field dependence of the material’s resistivity starts to increase. An analysis of the infrared reflectivity spectrum at T = 295 K allows us to resolve the main phonon bands and intraband and interband transitions, and estimate indirect and direct band gaps of E_opt,i = 0.09 and E_opt,d = 0.33 eV, respectively, which are in good agreement with the theoretically predicted ones. The experimental band structure obtained by ARPES is nearly T independent above and below T_N . The comparison of the theoretical and experimental data shows a weak intermixing of the Eu 4f states close to the point with the bands formed by the phosphorous 3p orbitals leading to an induction of a small magnetic moment at the P sites.
42 4 - Research DataData for Inflammatory biotype of ADHD is linked to chronic stress: a data-driven analysis of the inflammatory pro-teome2023Protein Data and Grouping variable for the Article "Inflammatory biotype of ADHD is linked to chronic stress: a data-driven analysis of the inflammatory proteome" published in Translational Psychiatry
66 13 - Research DataData for: Influence of magnetism, strain and pressure on the band topology of EuCd2As22023-11-08Motivated by the wealth of proposals and realizations of nontrivial topological phases in EuCd2As2, such as a Weyl semimetallic state and the recently discussed semimetallic versus semiconductor behavior in this system, we analyze in this work the role of the delicate interplay of Eu magnetism, strain and pressure on the realization of such phases. For that we invoke a combination of a group theoretical analysis with ab initio density functional theory calculations and uncover a rich phase diagram with various non-trivial topological phases beyond a Weyl semimetallic state, such as axion and topological crystalline insulating phases, and discuss their realization.
28 3 - Research DataEffect of stem design and positioning on the leg axis after total hip arthroplasty: a secondary analysis2024Abstract: Background/Objectives: Various parameters, like femoral offset and leg length, are associated with good patient outcomes after total hip arthroplasty. In this prospective study, the effects of stem design, its placement in the proximal femur and the resulting femoral offset on the total leg axis were investigated. Methods: The 27 patients included in this study received biplanar radiography (EOS® Imaging) with 3D reconstruction using sterEOS software both preoperatively and postoperatively. For all leg alignment parameters obtained from the 3D reconstruction and from measurements using mediCAD, the deltas between the postoperative and preoperative values were determined. Patients were divided into those who received a short-stem prosthesis and those who received a straight-stem prosthesis. Results: The change in femoral offset with the implantation of a short-stem prosthesis was significantly greater than that with the implantation of a straight-stem prosthesis (11.4 ± 5.9 vs. 4.6 ± 7.4 mm, p = 0.014). Compared with the straight-stem implantation, short-stem implantation caused a significantly greater increase in the varus orientation of the leg (-1.4 ± 0.9 vs. -0.4 ± 1.4 °, p = 0.048). There was no significant difference in the positioning of the short-stem prosthesis compared to the straight-stem prosthesis in the proximal femur (3.6 ± 3.1 vs. 2.6 ± 1.9 °, p = 0.317). Conclusions: These findings substantiate the impact of prosthesis design on offset and leg alignment. The implantation of short-stems is more variable and requires precise planning. Intraoperative non-physiological offset changes and varus deviation of the leg axis should be avoided. Trial registration: The study was retrospectively registered with the German Clinical Trials Register (DRKS) under the number DRKS00015053 on the 1st of August 2018.
29 3 - Research DataIsothermal Compressibility and Isobaric Thermal Expansion of Liquid trans-1,2-Dichloroethene at Low Temperatures2024-03-27This dataset includes the experimental data on the density of the trans-1,2-dichloroethene. Thermal expansion and isothermal compressibility of this material were measured in the pressure range of 1—150 bar and temperature range from -26 to +6 °C. X-ray radiography set-up HECTOR at Ghent University was used for these measurements.
70 7 - Research DataMDH_SmallFindPhotos2023-09Edelmann, Pascal (DataCollector)Hofmann, Andreas (DataCollector)Hochrieser, Stefanie (DataCollector)Möbius, Merle (DataCollector)Biezeveld, Irini (DataCollector)Grün, Fabian (DataCollector)Kluge, Jonas (DataCollector)Koch, Katharina (DataCollector)Mez, Nathalie (DataCollector)Maiorano, Maria Pia (DataCollector)Schneider, Tamara (DataCollector)Zöchling, Antje (DataCollector)Juhas, Marcel (DataCollector)Özcelik, Taylan (DataCollector)Puerta Schardt, Juan-Marco (DataCollector)Schweizer, Moyra (DataCollector)Göbel, Jonas (DataCollector)Budzyn, Adrian (DataCollector)Werner, Jannis (DataCollector)Öztürk, Mahsa (DataCollector)Greven, Sofia (DataCollector)Schmidt, Conrad (DataCollector)The Al-Mudhaybi Regional Survey was initiated to gain insights into settlement patterns, their development, and the causes of significant social changes in Central Oman, particularly during the 3rd millennium BCE. This was achieved through a combination of survey methods (remote sensing based on satellite imagery with ground-truthing and intensive systematic surveys in north-south transects) as well as small-scale excavations. The results challenged the previous notion of traditional settlement hierarchies and a predominantly sedentary, agriculture-based society in Central Oman, especially during the Early Bronze Age (Umm an-Nar period). In-stead, a complex network of temporary sites emerged, utilized at various times and for different activities. Another significant finding is that the interior of Oman was more heavily frequented during the Neolithic period than previously believed. Additionally, contrary to prior assumptions, the Middle Bronze Age (Wadi Suq period) does not represent a period of decline and shares similarities in its development with the northern regions of the Omani Peninsula. These findings can contribute to raising awareness of the diversity of human lifestyles overall, particularly highlighting the cultural achievements of mobile communities.
29 4 - Research DataMDH_SmallFinds2023-10Kluge, Jonas (DataCollector)Edelmann, Pascal (DataCollector)Hofmann, Andreas (DataCollector)Hochrieser, Stefanie (DataCollector)Möbius, Merle (DataCollector)Maiorano, Maria Pia (DataCollector)Biezeveld, Irini (DataCollector)Billor, Beriwan (DataCollector)Grün, Fabian (DataCollector)Mez, Natalie (DataCollector)Schweizer, Moyra (DataCollector)Schmidt, Conrad (DataCollector)Budzyn, Adrian (DataCollector)Werner, Jannis (DataCollector)Göbel, Jonas (DataCollector)Öztürk, Mahsa (DataCollector)Greven, Sofia (DataCollector)The Al-Mudhaybi Regional Survey was initiated to gain insights into settlement patterns, their development, and the causes of significant social changes in Central Oman, particularly during the 3rd millennium BCE. This was achieved through a combination of survey methods (remote sensing based on satellite imagery with ground-truthing and intensive systematic surveys in north-south transects) as well as small-scale excavations. The results challenged the previous notion of traditional settlement hierarchies and a predominantly sedentary, agriculture-based society in Central Oman, especially during the Early Bronze Age (Umm an-Nar period). In-stead, a complex network of temporary sites emerged, utilized at various times and for different activities. Another significant finding is that the interior of Oman was more heavily frequented during the Neolithic period than previously believed. Additionally, contrary to prior assumptions, the Middle Bronze Age (Wadi Suq period) does not represent a period of decline and shares similarities in its development with the northern regions of the Omani Peninsula. These findings can contribute to raising awareness of the diversity of human lifestyles overall, particularly highlighting the cultural achievements of mobile communities.
22 1 - Research DataMDH_Structures2023-09Edelmann, Pascal (DataCollector)Hofmann, Andreas (DataCollector)Hochrieser, Stefanie (DataCollector)Möbius, Merle (DataCollector)Maiorano, Maria Pia (DataCollector)Biezeveld, Irini (DataCollector)Billor, Beriwan (DataCollector)Grün, Fabian (DataCollector)Kluge, Jonas (DataCollector)Koch, Katharina (DataCollector)Mez, Natalie (DataCollector)Schneider, Tamara (DataCollector)Zöchling, Antje (DataCollector)Juhas, Marcel (DataCollector)Özcelik, Taylan (DataCollector)Puerta-Schardt, Juan-Marco (DataCollector)Schweizer, Moyra (DataCollector)Schmidt, Conrad (DataCollector)Göbel, Jonas (DataCollector)Budzyn, Adrian (DataCollector)Werner, Jannis (DataCollector)Öztürk, Mahsa (DataCollector)Greven, Sofia (DataCollector)The Al-Mudhaybi Regional Survey was initiated to gain insights into settlement patterns, their development, and the causes of significant social changes in Central Oman, particularly during the 3rd millennium BCE. This was achieved through a combination of survey methods (remote sensing based on satellite imagery with ground-truthing and intensive systematic surveys in north-south transects) as well as small-scale excavations. The results challenged the previous notion of traditional settlement hierarchies and a predominantly sedentary, agriculture-based society in Central Oman, especially during the Early Bronze Age (Umm an-Nar period). In-stead, a complex network of temporary sites emerged, utilized at various times and for different activities. Another significant finding is that the interior of Oman was more heavily frequented during the Neolithic period than previously believed. Additionally, contrary to prior assumptions, the Middle Bronze Age (Wadi Suq period) does not represent a period of decline and shares similarities in its development with the northern regions of the Omani Peninsula. These findings can contribute to raising awareness of the diversity of human lifestyles overall, particularly highlighting the cultural achievements of mobile communities.
36 2 - Research DataMicroscopic analysis of the valence transition in tetragonal EuPd2Si22023-02-23Under temperature or pressure tuning, tetragonal EuPd2Si2 is known to undergo a valence transition from nearly divalent to nearly trivalent Eu accompanied by a volume reduction. Albeit intensive work, its microscopic origin is still being discussed. Here, we investigate the mechanism of the valence transition under volume compression by ab initio density functional theory (DFT) calculations. Our analysis of the electronic and magnetic properties of EuPd2Si2 when approaching the valence transition shows an enhanced c−f hybridization between localized Eu 4f states and itinerant conduction states (Eu 5d, Pd 4d, and Si 3p) where an electronic charge redistribution takes place. We observe that the change in the electronic structure is intimately related to the volume reduction where Eu-Pd(Si) bond lengths shorten and, for the transition to happen, we trace the delicate balance between electronic bandwidth, crystal field splitting, Coulomb repulsion, Hund's coupling and spin-orbit coupling. In a next step we compare and benchmark our DFT results to surface-sensitive photoemission data in which the mixed-valent properties of EuPd2Si2 are reflected in a simultaneous observation of divalent and trivalent signals from the Eu 4f shell. The study serves as well to explore the limits of density functional theory and the choice of exchange correlation functionals to describe such a phenomenon as a valence transition.
18 4 - Research DataMolecular Mechanisms and Evolutionary Robustness of a Color Switch in Proteorhodopsins2023-10-17Mao, JiafeiThe data set is associated with manuscript: Jiafei Mao, Xinsheng Jin, Man Shi, David Heidenreich, Lynda J. Brown, Richard C.D. Brown, Moreno Lelli, Xiao He, Clemens Glaubitz: Molecular Mechanisms and Evolutionary Robustness of a Color Switch in Proteorhodopsins; submitted to Science Advances (adj0384). It contains the NMR data from Figures 2, 3, 4, S2-15 as well as data for the bioinformatics analysis in Figues 1d, 7, S22-S24. An overview of all samples and spectra is provided in Table S1 of the manuscript.
77 17 - Research DataMoment canting and domain effects in antiferromagnetic DyRh2Si22023-10-25A combined experimental and theoretical study of the layered antiferromagnetic compound DyRh2Si2 in the ThCr2Si2-type structure is presented. The heat capacity shows two transitions upon cooling: The first one at the Néel temperature TN = 55 K and a second one at TN2 = 12 K. Using magnetization measurements, we study the canting process of the Dy moments upon changing the temperature and can assign TN2 to the onset of the canting of the magnetic moments towards the [100] direction away from the c axis. Furthermore, we found that the field dependence of the magnetization is highly anisotropic and shows a two-step process for H || 001. We used a mean-field model to determine the crystalline electric field as well as the exchange interaction parameters. Our magnetization data together with the calculations reveal a moment orientation close to the [101] direction in the tetragonal structure at low temperatures and fields. Applying photoemission electron microscopy, we explore the (001) surface of the cleaved DyRh2Si2 single crystal and visualize Si- and Dy-terminated surfaces. Our results indicate that the Si-Rh-Si surface protects the deeper lying magnetically active Dy layers and is thus attractive for investigation of magnetic domains and their properties in the large family of LnT2Si2 materials.
33 8 - Research DataRaumkonstruktionen im Kontext sozialer Medien: Selbsteinschaetzungen von Lehramtsstudierenden der Geographie2023-12-08Through the ambiguity of the digital, topics for Geography teacher education are being reconfigured. An example of this are constructions of space on social media. Here, teachers require specific knowledge and abilities. Against the backdrop of the TPACK Model, a corresponding test-instrument for pre-service teachers was developed and applied between January and May 2021. Confirmatory factor analysis confirms the TPACK model as an appropriate fit for the data. In the realms of pedagogical knowledge, pre-service teachers working as substitute teachers display higher self-evaluated knowledge and abilities compared to their counterparts who do not hold such a position. Tendencies towards self-evaluated TPACK growth can be identified over the course of students’ studies. The documents attached include the data set as well as the workflow applied in R to test construct validity and hypotheses on self-evaluated pedagogical knowledge and TPACK development over time.
102 23 - Research DataReverse quantum annealing assisted by forward annealing2024-07Quantum annealers conventionally use forward annealing to generate heuristic solutions. Reverse annealing can potentially generate better solutions but necessitates an appropriate initial state. Ways to find such states are generally unknown or highly problem dependent, offer limited success and severely restrict the scope of reverse annealing. We propose a general method that improves the overall solution quality and quantity by feeding reverse annealing with low quality solutions obtained from forward annealing. Experimental demonstration of solving the graph coloring problem using the D-Wave quantum annealers shows that our method is able to convert invalid solutions obtained from forward annealing to at least one valid solution obtained after assisted reverse annealing for 57% of 459 random Erdős-Rényi graphs. Our method significantly outperforms random initial states, obtains more unique solutions on average, and widens the applicability of reverse annealing. Although the average number of valid solutions obtained drops exponentially with the problem size, a scaling analysis for the graph coloring problem shows that our method effectively extends the computational reach of conventional forward annealing using reverse annealing.
19 2 - Research DataSection-Type Constraints on the Choice of Linguistic Mechanisms in Research Articles: A Corpus-Based Approach2023This thesis investigates the structure of research articles in the field of Computational Linguistics with the goal of establishing that a set of distinctive linguistic features is associated with each section type. The empirical results of the study are derived from the quantitative and qualitative evaluation of research articles from the ACL Anthology Corpus. More than 20,000 articles were analyzed for the purpose of retrieving the target section types and extracting the predefined set of linguistic features from them. Approximately 1,100 articles were found to contain all of the following five section types: abstract, introduction, related work, discussion, and conclusion. These were chosen for the purpose of comparing the frequency of occurrence of the linguistic features across the section types. Making use of frameworks for Natural Language Processing, the Stanford CoreNLP Module, and the Python library SpaCy, as well as scripts created by the author, the frequency scores of the features were retrieved and analyzed with state-of-the-art statistical techniques. The results show that each section type possesses an individual profile of linguistic features which are associated with it more or less strongly. These section-feature associations are shown to be derivable from the hypothesized purpose of each section type. Overall, the findings reported in this thesis provide insights into the writing strategies that authors employ so that the overall goal of the research paper is achieved. The results of the thesis can find implementation in new state-of-the-art applications that assist academic writing and its evaluation in a way that provides the user with a more sophisticated, empirically based feedback on the relationship between linguistic mechanisms and text type. In addition, the potential of the identification of text-type specific linguistic characteristics (a text-feature mapping) can contribute to the development of more robust language-based models for disinformation detection.
218 7 - Research DataStructural response of G protein binding to the cyclodepsipeptide inhibitor FR900359 probed by NMR spectroscopy2024-07-04Christian BoniferThe cyclodepsipeptide FR900359 (FR) and its analogs are able to selectively inhibit the class of Gq proteins by blocking GDP/GTP exchange. The inhibitor binding site of Gq has been characterized by X-ray crystallography, and various binding and functional studies have determined binding kinetics and mode of inhibition. Here we investigate isotope-labeled FR bound to the membrane-anchored G protein heterotrimer by solid-state nuclear magnetic resonance (ssNMR) and in solution by liquid-state NMR. The resulting data allowed us to identify regions of the inhibitor which show especially pronounced effects upon binding and revealed a generally rigid binding mode in the cis conformation under native-like conditions. The inclusion of the membrane environment allowed us to show a deep penetration of FR into the lipid bilayer illustrating a possible access mode of FR into the cell. Dynamic nuclear polarization (DNP)-enhanced ssNMR was used to observe the structural response of specific segments of the Gα subunit to inhibitor binding. This revealed rigidification of the switch I binding site and an allosteric response in the α5 helix as well as suppression of structural changes induced by nucleotide exchange due to inhibition by FR. Our NMR studies of the FR-G protein complex conducted directly within a native membrane environment provide important insights into the inhibitors access via the lipid membrane, binding mode, and structural allosteric effects.
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