MEMS Product Engineering

Multiorbital effects in the functional renormalization group: A weak-coupling study of the Emery model

“…6). Such a simultaneous occurrence of incommensurability in the magnetic channel and a deformation of the fermion-boson vertex in the Cooper channel has already been observed in the one-band (t, t ′ ) Hubbard model 42 and may be explained as follows. Consider a singlet Copper pair with momenta (k, −k) scattered to (k ′ , −k ′ ) by the interaction in the Cooper channel which shall be mimicked by a one-loop particle-particle diagram with two spin-channel vertices.…”

“…Note that, close to the transition from d x 2 −y 2 -wave SC to ferromagnetism in the one-band Hubbard model, this resolution would be still too coarse in the fermionic momenta. 42 For the parameters considered in this work, however, we are far away from such a transition and a deformation of the form factors at low energies should at least qualitatively be captured within our approach.…”

“…At least for the one-band Hubbard model, the above approximations seem to be fine in a large region of the parameter space. 42 The question now is, whether important orbital makeup effects are still captured within a viable truncation of an FFE.…”

“…These ansätze have been found to describe the weak momentum dependences well in large parts of the phase diagram with the exception of a region around the transition from d-wave SC to ferromagnetism (FM). 42 Let us note in passing that also graphene and the kagome lattice models have recently been studied within a related channel-decomposed fRG treatment, dubbed singular-mode-fRG (SMFRG). 43,44 As for fRG studies of models for Copper oxide planes, the phase diagrams in Ref.…”

Modeling, Simulation and Characterization of Aluminum Implantation in 4H-SiC for Large-Area Photodiode Technology

“…Therefore the computer assisted analysis of simulation results based on modelling is so important to reduce time and costs of technology development [8][9][10]. (225) Typical ion implantation processes are performed at room temperature, but high fluences of implanted ions (above 10 16 cm −2 ) result in high radiation damage hard to recover even under high temperature postimplantation annealing process (PIA).…”