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TT: Tiefe Temperaturen
TT 13: Systeme korrelierter Elektronen: Theorie II
TT 13.7: Talk
Wednesday, March 26, 2003, 16:15–16:30, HSZ304
High-frequency corrected QMC simulations within the DMFT — •Carsten L. Knecht, Nils Blümer, and P.G.J. van Dongen — Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudinger Weg 7, 55099 Mainz, Germany
The Quantum Monte-Carlo(QMC) solution of the impurity model within the Dynamical Mean Field Theory(DMFT) self-consistency scheme produces discretized imaginary time Green’s functions. Special effort is needed to avoid high-frequency artifacts in the Fourier transform to Matsubara frequencies. By combining a high-frequency expansion of the self-energy with the discretized numerical data, we obtain the exact asymptotic behavior of the self-energy up to order 1/ω (and for the Green’s function to order 1/ω3). Using this improved method, enabling us to calculate physical quantities such as the double occupancy or spectral functions with higher precision and less numerical effort, we present new results concerning the Mott-Hubbard metal-insulator transition.