@article{SeiboldLorenzana, author = {Seibold, G{\"o}tz and Lorenzana, Jos{\´e}}, title = {Time-dependent Gutzwiller approximation for the Hubbard Model}, language = {en} } @article{SchmeisserSeiboldReif, author = {Schmeißer, Dieter and Seibold, G{\"o}tz and Reif, J{\"u}rgen}, title = {Nano-scaled Dielectric Barriers (NanoDieB) for CMOS compatible Si-technologies}, series = {Forum der Forschung}, journal = {Forum der Forschung}, number = {19}, issn = {0947-6989}, pages = {131 -- 136}, language = {en} } @misc{Seibold, author = {Seibold, G{\"o}tz}, title = {On the Evaluation of Higher-Harmonic-Current Responses for High-Field Spectroscopies in Disordered Superconductors}, series = {Condensed Matter}, volume = {8}, journal = {Condensed Matter}, number = {4}, issn = {2410-3896}, doi = {10.3390/condmat8040095}, pages = {1 -- 16}, abstract = {We discuss a formalism that allows for the calculation of a higher-harmonic-current response to a strong applied electric field for disordered superconducting systems described on the basis of tight-binding models with on- and/or intersite interactions. The theory is based on an expansion of the density matrix in powers of the field amplitudes, where we solve the equation of motion for the individual components. This allows the evaluation of higher-order response functions on significantly larger lattices than one can achieve with a previously used approach, which is based on a direct temporal integration of the equation of motion for the complete density matrix. In the case of small lattices, where both methods can be applied by including also the contribution of collective modes, we demonstrate the agreement of the corresponding results.}, language = {en} } @misc{HokampSeibold, author = {Hokamp, Sascha and Seibold, G{\"o}tz}, title = {Tax Compliance and Public Goods Provision An Agent-based Econophysics Approach}, series = {Central European Journal of Economic Modelling and Econometrics}, volume = {6}, journal = {Central European Journal of Economic Modelling and Econometrics}, number = {4}, issn = {2080-0886}, pages = {217 -- 236}, abstract = {We calculate the dynamics of tax evasion within a multi-agent econophysics model which is adopted from the theory of magnetism and previously has been shown to capture the main characteristics from agent-based based models which build on the standard Allingham and Sandmo approach. In particular, we implement a feedback of public goods provision on the decision-making of selfish agents which aim to pursue their self interest. Our results imply that such a feedback enhances the moral attitude of selfish agents thus reducing the percentage of tax evasion. Two parameters govern the behavior of selfish agents, (i) the rate of adaption to changes in public goods provision and (ii) the threshold of perception of public goods provision. Furtheron we analyze the tax evasion dynamics for different agent compositions and under the feedback of public goods provision. We conclude that policymakers may enhance tax compliance behavior via the threshold of perception by means of targeted public relations.}, language = {en} } @misc{SeiboldPickhardt, author = {Seibold, G{\"o}tz and Pickhardt, Michael}, title = {Lapse of time effects on tax evasion in an agent-based econophysics model}, series = {Physica A: Statistical Mechanics and its Applications}, volume = {392}, journal = {Physica A: Statistical Mechanics and its Applications}, number = {9}, issn = {0378-4371}, doi = {10.1016/j.physa.2013.01.016}, pages = {2079 -- 2087}, abstract = {We investigate an inhomogeneous Ising model in the context of tax evasion dynamics where different types of agents are parameterized via local temperatures and magnetic fields. In particular, we analyze the impact of lapse of time effects (i.e. backauditing) and endogenously determined penalty rates on tax compliance. Both features contribute to a microfoundation of agent-based econophysics models of tax evasion.}, language = {en} } @misc{GuentherSeibold, author = {G{\"u}nther, Falk and Seibold, G{\"o}tz}, title = {Elektronische Inhomogenit{\"a}ten in Hochtemperatursupraleitern}, series = {Forum der Forschung}, volume = {9}, journal = {Forum der Forschung}, number = {18}, issn = {0947-6989}, pages = {41 -- 48}, language = {de} } @misc{SeiboldVarlamov, author = {Seibold, G{\"o}tz and Varlamov, Sergej}, title = {Effect of incommensurate charge-density wave scattering on theelectronic structure of high-Tc cuprates (II)}, series = {Journal of Superconductivity}, volume = {15}, journal = {Journal of Superconductivity}, number = {6}, issn = {0896-1107}, pages = {505 -- 506}, language = {en} } @article{SigmundSeiboldBilletal., author = {Sigmund, Ernst and Seibold, G{\"o}tz and Bill, Andreas and Wulf, Ulrich and Isenmann, G. and Essl, W.}, title = {Dynamische Eigenschaften von Festk{\"o}rpern und Molekularen Strukturen}, language = {en} } @article{SeiboldSigmund, author = {Seibold, G{\"o}tz and Sigmund, Ernst}, title = {Gutzwiller and Slave-Boson Methods for Intersite Coulomb Interactions}, language = {en} } @phdthesis{Seibold, author = {Seibold, G{\"o}tz}, title = {Spin-polarisierte Quasiteilchen in der Hochtemperatursupraleitung}, publisher = {Aachen : Shaker}, language = {de} } @article{SigmundHizhnyakovSeibold, author = {Sigmund, Ernst and Hizhnyakov, Vladimir and Seibold, G{\"o}tz}, title = {Electronic Phase Separation in High-Tc Superconductors}, language = {en} } @article{RuckhSeiboldSigmund, author = {Ruckh, R. and Seibold, G{\"o}tz and Sigmund, Ernst}, title = {Influence of quantum fluctuations on solitary-wave acoustic polaron motion}, language = {en} } @article{SeiboldSigmund, author = {Seibold, G{\"o}tz and Sigmund, Ernst}, title = {Metal-insulator transition in doped bismuthate superconductors}, language = {en} } @article{SeiboldSigmundHizhnyakov, author = {Seibold, G{\"o}tz and Sigmund, Ernst and Hizhnyakov, Vladimir}, title = {Spin-cluster states in CuO2 planes}, series = {Physical review B}, volume = {48}, journal = {Physical review B}, number = {10}, issn = {0556-2805}, pages = {7537 -- 7544}, language = {en} } @article{SeiboldVarlamov, author = {Seibold, G{\"o}tz and Varlamov, Sergej}, title = {Effective particle-particle interaction in incommensurable CDW systems}, language = {en} } @misc{SeiboldCapraraGrillietal., author = {Seibold, G{\"o}tz and Caprara, Sergio and Grilli, Marco and Raimondi, Roberto}, title = {Theory of the Spin Galvanic Effect at Oxide Interfaces}, series = {Physical Review Letters}, volume = {119}, journal = {Physical Review Letters}, number = {25}, issn = {1092-0145}, doi = {10.1103/PhysRevLett.119.256801}, abstract = {The spin galvanic effect (SGE) describes the conversion of a nonequilibrium spin polarization into a transverse charge current. Recent experiments have demonstrated a large conversion efficiency for the two-dimensional electron gas formed at the interface between two insulating oxides, LaAlO3 and SrTiO3. Here, we analyze the SGE for oxide interfaces within a three-band model for the Ti t2g orbitals which displays an interesting variety of effective spin-orbit couplings in the individual bands that contribute differently to the spin-charge conversion. Our analytical approach is supplemented by a numerical treatment where we also investigate the influence of disorder and temperature, which turns out to be crucial to providing an appropriate description of the experimental data.}, language = {en} } @misc{SeiboldUdinaCastellanietal., author = {Seibold, G{\"o}tz and Udina, Mattia and Castellani, Claudio and Benfatto, Lara}, title = {Third harmonic generation from collective modes in disordered superconductors}, series = {Physical Review B}, volume = {103}, journal = {Physical Review B}, number = {1}, doi = {10.1103/PhysRevB.103.014512}, pages = {19}, abstract = {Recent experiments with strong THz fields in both conventional and unconventional superconductors have clearly evidenced a marked third-harmonic generation below the superconducting temperature Tc. Its interpretation challenged substantial theoretical work aimed at establishing the relative efficiency of quasiparticle excitations and collective modes in triggering such a resonant response. Here we compute the nonlinear current by implementing a time-dependent Bogoljubov-de Gennes approach, with the twofold aim to account nonperturbatively for the effect of local disorder, and to include the contribution of all collective modes, i.e., superconducting amplitude (Higgs) and phase fluctuations, and charge fluctuations. We show that, in agreement with previous work, already at small disorder the quasiparticle response is dominated by paramagnetic effects. We further demonstrate that paramagnetic processes mediate also the response of all collective modes, with a substantial contribution of charge/phase fluctuations. These processes, which have been overlooked so far, turn out to dominate the third-order current at strong disorder. In addition, we show that disorder strongly influences the polarization dependence of the nonlinear response, with a marked difference between the clean and the disordered case. Our results are particularly relevant for recent experiments in cuprates, whose band structure is in a first approximation reproduced by our lattice model.}, language = {en} } @misc{SeiboldCastellaniLorenzana, author = {Seibold, G{\"o}tz and Castellani, Claudio and Lorenzana, Jos{\´e}}, title = {Adiabatic transition from a BCS superconductor to a Fermi liquid and phase dynamics}, series = {Physical Review B}, volume = {105}, journal = {Physical Review B}, number = {18}, issn = {2469-9969}, doi = {10.1103/PhysRevB.105.184513}, pages = {184513-1 -- 184513-14}, abstract = {We investigate the physics of an adiabatic transition from a BCS superconductor to a Fermi liquid for an exponentially slow decreasing pairing interaction. We show that, depending on the order of the thermodynamic limit and large times, a situation can arise in which the Fermi liquid keeps a memory of the parent BCS state. Furthermore, a time inversion of the interaction, supplemented by a manipulation analogous to a spin-/photon-echo experiment, allows us to recover the parent BCS state. Moreover, we study the evolution of the order parameter phase ϕ in transforming the BCS superconductor to a conventional metal. Since the global phase is the conjugate variable of the density, we explicitly show how to use the dynamics of ϕ together with gauge invariance to build up the noninteracting chemical potential away from particle-hole symmetry. We further analyze the role of ϕ in restoring the gauge-invariant current response when the noninteracting Fermi liquid is approached starting from a BCS superconductor in the presence of an external vector field.}, language = {en} } @misc{CapraraDiCastroMirarchietal., author = {Caprara, Sergio and Di Castro, Carlo and Mirarchi, Giovanni and Seibold, G{\"o}tz and Grilli, Marco}, title = {Dissipation-driven strange metal behavior}, series = {Communications Physics}, journal = {Communications Physics}, number = {5}, issn = {2399-3650}, doi = {10.1038/s42005-021-00786-y}, pages = {1 -- 7}, abstract = {Anomalous metallic properties are often observed in the proximity of quantum critical points, with violation of the Fermi Liquid paradigm. We propose a scenario where, near the quantum critical point, dynamical fluctuations of the order parameter with finite correlation length mediate a nearly isotropic scattering among the quasiparticles over the entire Fermi surface. This scattering produces a strange metallic behavior, which is extended to the lowest temperatures by an increase of the damping of the fluctuations. We phenomenologically identify one single parameter ruling this increasing damping when the temperature decreases, accounting for both the linear-in-temperature resistivity and the seemingly divergent specific heat observed, e.g., in high-temperature superconducting cuprates and some heavy-fermion metals.}, language = {en} } @misc{SeiboldArpaiaYingYingetal., author = {Seibold, G{\"o}tz and Arpaia, Riccardo and Ying Ying, Peng and Fumagalli, Roberto and Braicovich, Lucio and Di Castro, Carlo and Grilli, Marco and Ghiringhelli, Giacomo Claudio and Caprara, Sergio}, title = {Strange metal behaviour from charge density fluctuations in cuprates}, series = {Communications Physics}, volume = {4}, journal = {Communications Physics}, issn = {2399-3650}, doi = {10.1038/s42005-020-00505-z}, pages = {1 -- 6}, abstract = {Besides the mechanism responsible for high critical temperature superconductivity, the grand unresolved issue of the cuprates is the occurrence of a strange metallic state above the so-called pseudogap temperature T*. Even though such state has been successfully described within a phenomenological scheme, the so-called Marginal Fermi-Liquid theory, a microscopic explanation is still missing. However, recent resonant X-ray scattering experiments identified a new class of charge density fluctuations characterized by low characteristic energies and short correlation lengths, which are related to the well-known charge density waves. These fluctuations are present over a wide region of the temperature-vs-doping phase diagram and extend well above T*. Here we investigate the consequences of charge density fluctuations on the electron and transport properties and find that they can explain the strange metal phenomenology. Therefore, charge density fluctuations are likely the long-sought microscopic mechanism underlying the peculiarities of the metallic state of cuprates.}, language = {en} }