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Remote Sensing Indicators: Vegetation Cover
No full textPredicted monthly vegetation cover dataset in a spatial resolution of 1 x 1 km based on MODIS and AVHRR datasets. For predicting the retrospective vegetation cover classes the STARFM algorithm was utilized in a Python environment. All available months are packed into one .zip file which can be (i) downloaded and (ii) extracted using free and open standard software (e.g. 7-zip)
Bias-Free Access to Orbital Angular Momentum in Two-Dimensional Quantum Materials
No full textRaw data used for the manuscript: 'Bias-Free Access to Orbital Angular Momentum in Two-Dimensional Quantum Materials' published in Physical Review Letters 2024. Data folders are organized as figures appearing in the publication. Please read the corresponding 'README' file attached to each figure subfolder.(Other) We are grateful for funding support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy through the Würzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter ct.qmat (EXC 2147, Project ID 390858490) as well as through the Collaborative Research Center SFB 1170 ToCoTronics (Project ID 258499086)
Manipulating topology of quantum phase transitions by symmetry enhancement
No full textProcessed data used for generating the figures of manuscript: "Manipulating topology of quantum phase transitions by symmetry enhancement" on arXiv: https://arxiv.org/abs/2410.05059. Please read the 'README' file.We are grateful for funding support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy through the Würzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter ct.qmat (EXC 2147, Project ID 390858490) as well as through the Collaborative Research Center SFB 1170 ToCoTronics (Project ID 258499086)
Hubbard and Heisenberg models on hyperbolic lattices - Metal-insulator transitions, global antiferromagnetism and enhanced boundary fluctuations
No full textProcessed data used for generating the figures of manuscript: "Hubbard and Heisenberg models on hyperbolic lattices - Metal-insulator transitions, global antiferromagnetism and enhanced boundary fluctuations" on arXiv: https://arxiv.org/abs/2406.03416. Please read the 'README' file.We are grateful for funding support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy through the Würzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter ct.qmat (EXC 2147, Project ID 390858490) as well as through the Collaborative Research Center SFB 1170 ToCoTronics (Project ID 258499086)
Spin Spiral State at a Ferromagnetic Gd Vacuum Interface
No full textCentrosymmetric bulk magnets made of layered Gd intermetallics had been discovered recently to exhibit helical spin spirals with a wavelength of ≈2 nm that transform into skyrmion lattices at certain magnetic fields. Here we report on the observation of a spin spiral state at the Gd(0001) surface. Spinpolarized scanning tunneling microscopy images show striped regions with a periodicity of about 2 nm. These stripes rearrange upon application of an external magnetic field, thereby unambiguously confirming their magnetic origin. Density functional theory calculations explain that competing exchange interactions in the surface layer of Gd(0001) together with a magnetovolume fine-tuning of the exchange interaction to the next Gd layer favor a chiral 2 nm conical spin spiral at the surface, arising as a general behavior of the Gd monolayer.Please read the "README.txt" file for further information.We acknowledge financial support by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), S. B. through SFB 1238 Project No. 277146847 (project C01), M. B. through Project No. 510676484 (GZ: BO 1468/29-1), and under Germany’s Excellence Strategy through the Würzburg– Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter—ct.qmat (EXC 2147, Project No. 390858490). G. B. gratefully acknowledges computing time granted through JARA-HPC on the supercomputer JURECA at Forschungszentrum Jülich
Instanton gas approach to the Hubbard model
No full textWe consider a path integral formulation of the Hubbard model based on a Hubbard-Stratonovich transformation that couples the auxiliary field to the local electronic density. This decoupling is known to have a saddle-point structure that shows a remarkable regularity: The field configuration at each saddle point can be understood in terms of a set of elementary field configurations localized in space and imaginary time which we coin instantons. The interaction between instantons is short ranged. Here, we formulate a classical partition function for the instanton gas that has predictive power. For a given set of physical parameters, we can predict the distribution of instantons and show that the instanton number is sharply defined in the thermodynamic limit, thereby defining a unique dominant saddle point. Decoupling in the charge channel conserves SU(2) spin symmetry for each field configurations. Hence, the instanton approach provides an SU(2) spin-symmetric approximation to the Hubbard model. It fails, however, to capture the magnetic transition inherent to the Hubbard model on the honeycomb lattice despite being able to describe local moment formation. In fact, the instanton itself corresponds to local moment formation and concomitant short-ranged antiferromagnetic correlations. This aspect is also seen in the single particle spectral function that shows clear signs of the upper and lower Hubbard bands. Our instanton approach bears remarkable similarities to local dynamical approaches, such as dynamical mean-field theory, in the sense that it has the unique property of allowing for local moment formation without breaking the SU(2) spin symmetry. In contrast to local approaches, it captures short-ranged magnetic fluctuations. Furthermore, it also offers possibilities for systematic improvements by taking into account fluctuations around the dominant saddle point. Finally, we show that the saddle point structure depends upon the choice of lattice geometry. For the square lattice at half filling, the saddle-point structure reflects the itinerant to localized nature of the magnetism as a function of the coupling strength. The implications of our results for Lefschetz thimble approaches to alleviate the sign problem are also discussed.Please read the ReadMe.txt file in the provided .zip file for technical details about data processing and plotting.Funding was provided partially by Cluster of Excellence ct-qmat (Complexity and Topology in Quantum Matter
Extreme Temperature Range (etr)
No full textcdo -sub -yearmax TX.nc -yearmin TN.nc out.ncDifference between the maximum of the maximum temperature and the minimum of the minimum temperature: Let TXi be the daily maximum temperature on day i and TNj be the daily minimum temperature on day j. For etr build the difference between the maximum value of TXi per year and the minimum value of TNj per year
Standardized Precipitation Index (spi)
No full textA drought measure specified as a precipitation deficitStandardized Precipitation Index: A precipitation anomaly is considered relativ to the mean precipitation of a reference period (1981-2010) and based on the underlying statistical distribution (Gamma). The anomlies are considered over different months (3, 6, 9, 12). (More information under: https://climate-indices.readthedocs.io/en/latest/
Climate Indicators: Extremely Wet Days (r99p)
No full textcdo -yearpctl,99 RR.nc -yearmin RR.nc -yearmax RR.nc out.ncAnnual threshold for extreme heavy precipitation: Let RRt be the daily precipitation amount on day t. For R99p list all RRt of one year, take the 99th percentile value
Edge Zeros and Boundary Spinons in Topological Mott Insulators
No full textThis dataset contains the slave-rotor results for the Kane-Mele-Hubbard model presented in the publication. Each folder contains the data for a specific figure, provided as text files and the corresponding gnuplot scripts for creating the plots. Further information can be found in the readme files.We are grateful for funding support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy through the Würzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter ct.qmat (EXC 2147, Project ID 390858490) as well as through the Collaborative Research Center SFB 1170 ToCoTronics (Project ID 258499086)